diff --git a/src/CSET/cset_workflow/app/metplus_ascii2nc/file/nci/ascii2nc.conf b/src/CSET/cset_workflow/app/metplus_ascii2nc/file/nci/ascii2nc.conf
index f0f5dddf4..ee77d8c68 100644
--- a/src/CSET/cset_workflow/app/metplus_ascii2nc/file/nci/ascii2nc.conf
+++ b/src/CSET/cset_workflow/app/metplus_ascii2nc/file/nci/ascii2nc.conf
@@ -43,16 +43,8 @@ LEAD_SEQ =
 # https://metplus.readthedocs.io/en/latest/Users_Guide/systemconfiguration.html#directory-and-filename-template-info
 ###
 ASCII2NC_INPUT_DIR = {INPUT_BASE}
-ASCII2NC_INPUT_TEMPLATE = *.ascii
+ASCII2NC_INPUT_TEMPLATE = obs.{valid?fmt=%Y%m%dT%H%MZ}.ascii
 ASCII2NC_INPUT_FORMAT = met_point
 
 ASCII2NC_OUTPUT_DIR = {ENV[CYLC_WORKFLOW_SHARE_DIR]}/obs_nc
 ASCII2NC_OUTPUT_TEMPLATE = {valid?fmt=%Y%m%dT%H}.nc
-
-###
-# ASCII2NC Settings
-# https://metplus.readthedocs.io/en/latest/Users_Guide/wrappers.html#ascii2nc
-###
-
-ASCII2NC_WINDOW_BEGIN = 0
-ASCII2NC_WINDOW_END = 0
diff --git a/src/CSET/cset_workflow/app/metplus_point_stat/file/nci/pointstat.conf b/src/CSET/cset_workflow/app/metplus_point_stat/file/nci/pointstat.conf
index 5d7b1880d..a3d6ed571 100644
--- a/src/CSET/cset_workflow/app/metplus_point_stat/file/nci/pointstat.conf
+++ b/src/CSET/cset_workflow/app/metplus_point_stat/file/nci/pointstat.conf
@@ -36,10 +36,7 @@ INIT_TIME_FMT = %Y%m%dT%H
 INIT_BEG = {ENV[TASK_START_TIME]}
 INIT_END = {ENV[TASK_START_TIME]}
 INIT_INCREMENT = 1H
-LEAD_SEQ = begin_end_incr(0,{ENV[FORECAST_LENGTH]},1)
-
-# Number of seconds to shift times in the fcst file (try half the time increment)
-FCST_SHIFT = 1800
+LEAD_SEQ = begin_end_incr(4,{ENV[FORECAST_LENGTH]},1)
 
 ###
 # File I/O
diff --git a/src/CSET/cset_workflow/app/metplus_point_stat/file/nci/surface.conf b/src/CSET/cset_workflow/app/metplus_point_stat/file/nci/surface.conf
index d61168298..e1c42c5b4 100644
--- a/src/CSET/cset_workflow/app/metplus_point_stat/file/nci/surface.conf
+++ b/src/CSET/cset_workflow/app/metplus_point_stat/file/nci/surface.conf
@@ -17,7 +17,7 @@ POINT_STAT_FCST_FILE_TYPE = NETCDF_NCCF
 POINT_STAT_MESSAGE_TYPE = "ADPSFC"
 
 FCST_POINT_STAT_VAR1_NAME = air_temperature
-FCST_POINT_STAT_VAR1_LEVELS = "({valid?fmt=%Y%m%d_%H%M%S?shift={FCST_SHIFT}},*,*)"
+FCST_POINT_STAT_VAR1_LEVELS = "({valid?fmt=%Y%m%d_%H%M%S},*,*)"
 FCST_POINT_STAT_VAR1_THRESH = <=273, >273
 
 OBS_POINT_STAT_VAR1_NAME = t2m
@@ -25,7 +25,7 @@ OBS_POINT_STAT_VAR1_LEVELS = Z0
 OBS_POINT_STAT_VAR1_THRESH = <=273, >273
 
 FCST_POINT_STAT_VAR2_NAME = relative_humidity
-FCST_POINT_STAT_VAR2_LEVELS = "({valid?fmt=%Y%m%d_%H%M%S?shift={FCST_SHIFT}},*,*)"
+FCST_POINT_STAT_VAR2_LEVELS = "({valid?fmt=%Y%m%d_%H%M%S},*,*)"
 FCST_POINT_STAT_VAR2_THRESH =  <60, >95
 
 OBS_POINT_STAT_VAR2_NAME = rh2m
diff --git a/src/CSET/cset_workflow/app/metplus_prep_obs/bin/odb2/bom.py b/src/CSET/cset_workflow/app/metplus_prep_obs/bin/odb2/bom.py
index c587c32fb..8993b17ec 100644
--- a/src/CSET/cset_workflow/app/metplus_prep_obs/bin/odb2/bom.py
+++ b/src/CSET/cset_workflow/app/metplus_prep_obs/bin/odb2/bom.py
@@ -5,12 +5,13 @@
 patterns.
 """
 
+from abc import abstractmethod
 from typing import Iterable
 
 from metomi.isodatetime.data import TimePoint
 from pandas import DataFrame
 
-from .odb2 import PrepODB2, read_file, read_tarfile
+from .odb2 import PrepODB2
 
 # Valid bureau forecast systems
 BOM_SYSTEMS = ["access_g3", "access_g4"]
@@ -32,20 +33,30 @@ def __init__(self, system: str):
         Args:
             system: BOM system to source observations from (e.g. 'access_c3_dn')
         """
+        super().__init__()
         self.system = system
 
+        # Filter out observations rejected by OPS
+        self.odb_where += (
+            " AND ops_report_flags@hdr = 0 AND ops_datum_flags.b0@body = 0"
+        )
+
+    @abstractmethod
     def read_c3_type(self, type: str, valid_time: TimePoint) -> Iterable[DataFrame]:
         """Read C3 data pattern."""
         raise NotImplementedError
 
+    @abstractmethod
     def read_c4_type(self, type: str, valid_time: TimePoint) -> Iterable[DataFrame]:
         """Read C4 data pattern."""
         raise NotImplementedError
 
+    @abstractmethod
     def read_g3_type(self, type: str, valid_time: TimePoint) -> Iterable[DataFrame]:
         """Read G3 data pattern."""
         raise NotImplementedError
 
+    @abstractmethod
     def read_g4_type(self, type: str, valid_time: TimePoint) -> Iterable[DataFrame]:
         """Read G4 data pattern."""
         raise NotImplementedError
@@ -58,16 +69,16 @@ def read_type(self, type: str, valid_time: TimePoint) -> Iterable[DataFrame]:
             type: observation type (ODB2 file name without the suffix)
             valid_time: time to load
 
-        Returns an iterable of ODB2 DataFrames
+        Returns an iterable of ODB2 DataFrames containing all the observations for the given type and time.
         """
         if self.system.startswith("access_c3"):
-            yield from self.read_c3_type(type, valid_time)
+            return self.read_c3_type(type, valid_time)
         elif self.system.startswith("access_c4"):
-            yield from self.read_c4_type(type, valid_time)
+            return self.read_c4_type(type, valid_time)
         elif self.system.startswith("access_g3"):
-            yield from self.read_g3_type(type, valid_time)
+            return self.read_g3_type(type, valid_time)
         elif self.system.startswith("access_g4"):
-            yield from self.read_g4_type(type, valid_time)
+            return self.read_g4_type(type, valid_time)
 
     def read_odb(self, valid_time: TimePoint) -> Iterable[DataFrame]:
         """
@@ -76,7 +87,7 @@ def read_odb(self, valid_time: TimePoint) -> Iterable[DataFrame]:
         Args:
             valid_time: time to load
 
-        Returns an iterable of ODB2 DataFrames
+        Returns an iterable of ODB2 DataFrames containing all the observations for the given time.
         """
         if self.system.startswith("access_c"):
             for type in access_c_types:
@@ -107,25 +118,25 @@ def read_c3_type(self, type: str, valid_time: TimePoint) -> Iterable[DataFrame]:
         domain = self.system.split("_")[-1]
         tarfile = f"/g/data/ig2/odb2/access_c3/%Y/%m/%Y%m%dT%H%MZ/%Y%m%dT%H%MZ_{domain}_odb2.tar.zst"
         obsfile = f"ukv_odb2/{type}.odb"
-        return read_tarfile(tarfile, obsfile, valid_time)
+        return self.read_tarfile(tarfile, obsfile, valid_time)
 
     def read_c4_type(self, type: str, valid_time: TimePoint) -> Iterable[DataFrame]:
         """Read C4 data pattern."""
         domain = self.system.split("_")[-1]
         tarfile = f"/g/data/ig2/odb2/access_c4/%Y/%m/%Y%m%dT%H%MZ/%Y%m%dT%H%MZ_{domain}_odb2.tgz"
         obsfile = f"ukv_odb2/{type}.odb"
-        return read_tarfile(tarfile, obsfile, valid_time)
+        return self.read_tarfile(tarfile, obsfile, valid_time)
 
     def read_g3_type(self, type: str, valid_time: TimePoint) -> Iterable[DataFrame]:
         """Read G3 data pattern."""
         pattern = (
             "/g/data/ig2/odb2/access_g3/%Y/%m/%Y%m%dT%H%MZ/glm_odb2/{type}.odb.zst"
         )
-        return read_file(pattern, valid_time)
+        return self.read_file(pattern, valid_time)
 
     def read_g4_type(self, type: str, valid_time: TimePoint) -> Iterable[DataFrame]:
         """Read G4 data pattern."""
         pattern = (
             "/g/data/ig2/odb2/access_g4/%Y/%m/%Y%m%dT%H%MZ/glm_odb2/{type}.odb.zst"
         )
-        return read_file(pattern, valid_time)
+        return self.read_file(pattern, valid_time)
diff --git a/src/CSET/cset_workflow/app/metplus_prep_obs/bin/odb2/odb2.py b/src/CSET/cset_workflow/app/metplus_prep_obs/bin/odb2/odb2.py
index ad7f45110..68c426907 100644
--- a/src/CSET/cset_workflow/app/metplus_prep_obs/bin/odb2/odb2.py
+++ b/src/CSET/cset_workflow/app/metplus_prep_obs/bin/odb2/odb2.py
@@ -5,22 +5,30 @@
 """
 
 import functools
+import io
 import json
 import logging
+import shlex
+import subprocess
+import sys
+import tempfile
 from abc import ABC, abstractmethod
+from collections.abc import Iterable
+from contextlib import nullcontext
 from glob import glob
 from pathlib import Path
-from typing import Iterable, TextIO
+from typing import BinaryIO, TextIO
 
 import metomi.isodatetime.parsers
 import numpy
 import pandas
-import pyodc as odc
 from metomi.isodatetime.data import TimePoint
 from pandas import DataFrame
 
 try:
-    from compression import bz2, gzip, tarfile, zstd
+    import tarfile
+
+    from compression import bz2, gzip, zstd
 except ImportError:
     import bz2
     import gzip
@@ -139,6 +147,7 @@ def get_level(obs: DataFrame) -> pandas.Series:
     plevel = obs["vertco_reference_1@body"].where(
         obs["vertco_type@body"].isin([1, 11, 15]), numpy.nan
     )
+    plevel = plevel / 100  # Convert to hPa
 
     accumulated_fields = ["PRATE", "TSTM", "APCP", "NCPCP", "ACPCP"]
     if obs["name@varno"].isin(accumulated_fields).any():
@@ -200,17 +209,14 @@ def get_type(obs: DataFrame) -> pandas.Series:
 
 def odb2ascii_dataframe(obs: DataFrame) -> DataFrame:
     """
-    Convert a DataFrame from pyodc to MET ASCII format.
+    Convert a DataFrame from ODB2 to MET ASCII format.
 
     args:
-        obs: ODB2 data loaded with pyodb
+        obs: ODB2 dataframe to convert
 
     Output format is described at
     https://metplus.readthedocs.io/projects/met/en/latest/Users_Guide/reformat_point.html#id9
     """
-    # QC filter for only active values
-    obs = obs.loc[(obs["report_status@hdr"] | obs["datum_status@body"]) == 1]
-
     # Join in extra info
     obs = obs.join(varno_table(), on="varno@body")
     obs = obs.join(reporttype_table(), on="reportype@hdr")
@@ -253,54 +259,35 @@ def write_ascii(dataframe: DataFrame, output: TextIO):
     )
 
 
-def read_tarfile(tarpath: str, path: str, valid_time: TimePoint) -> Iterable[DataFrame]:
+def read_odb_sql(
+    stream: BinaryIO, columns: list[str], where: str | None = None
+) -> DataFrame:
     """
-    Read ODB2 data from a tarfile.
-
-    Paths can use strftime templates which will be replaced by valid_time
+    Read ODB2 data using ODC CLI.
 
     Args:
-        tarpath: path of the tarfile
-        path: path inside the tarfile
-        valid_time: used for pattern replacement
+        stream: Binary stream containing the ODB2 data
+        columns: List of columns to select
+        where: Optional SQL-like filter to apply to the data
     """
-    tarpath = valid_time.strftime(tarpath)
-    path = valid_time.strftime(path)
-    log.info("Reading %s:%s", tarpath, path)
+    sql = f"SELECT {', '.join(columns)}"
+    if where is not None:
+        sql += f" WHERE {where}"
 
-    with tarfile.open(tarpath, "r") as t:
-        f = t.extractfile(path)
-        yield from odc.read_odb(f)
+    with tempfile.NamedTemporaryFile(suffix=".odb2") as f:
+        f.write(stream.read())
+        f.flush()
 
+        cmd = ["odc", "sql", "-i", f.name, sql]
+        log.info("Running command: %s", shlex.join(cmd))
+        r = subprocess.run(cmd, stdout=subprocess.PIPE, text=True, check=True)
 
-def read_file(pattern: str, valid_time: TimePoint) -> Iterable[DataFrame]:
-    """
-    Read ODB2 data from a file, decompressing if required.
+    stream = io.StringIO(r.stdout)
 
-    Paths can use strftime templates which will be replaced by valid_time
-    Paths can use shell globs
-    Recognised extensions for decompression are .gz, .bz2, .zst
+    df = pandas.read_csv(stream, sep="\t", skipinitialspace=True)
+    df["statid@hdr"] = df["statid@hdr"].str.strip("'").str.strip()
 
-    Args:
-        path: path to open
-        valid_time: used for pattern replacement
-    """
-    path = valid_time.strftime(pattern)
-    log.info("Reading %s", path)
-
-    for p in glob(path):
-        if p.endswith(".gz"):
-            with gzip.open(p) as f:
-                yield from odc.read_odb(f)
-        elif p.endswith(".bz2"):
-            with bz2.open(p) as f:
-                yield from odc.read_odb(f)
-        elif p.endswith(".zst"):
-            with zstd.open(p) as f:
-                yield from odc.read_odb(f)
-        else:
-            with open(p, "rb") as f:
-                yield from odc.read_odb(f)
+    return df
 
 
 def valid_times_iterator(
@@ -335,18 +322,105 @@ class PrepODB2(ABC):
     ...    converter.odb2ascii(f, valid_times)
     """
 
+    def __init__(self, odb_where: str | None = None):
+        """Construct the converter."""
+        # ODB2 columns to read for each observation
+        self.odb_columns = [
+            "vertco_type@body",
+            "vertco_reference_1@body",
+            "varno@body",
+            "statid@hdr",
+            "date@hdr",
+            "time@hdr",
+            "lat@hdr",
+            "lon@hdr",
+            "stalt@hdr",
+            "obsvalue@body",
+            "reportype@hdr",
+        ]
+
+        # Optional SQL-like filter to apply to the data for QC filtering
+        self.odb_where = odb_where or "report_status@hdr = 1 AND datum_status@body = 1"
+
+    def read_tarfile(
+        self, tarpath: str, path: str, valid_time: TimePoint
+    ) -> Iterable[DataFrame]:
+        """
+        Read ODB2 data from a tarfile.
+
+        Paths can use strftime templates which will be replaced by valid_time
+
+        Args:
+            tarpath: path of the tarfile
+            path: path inside the tarfile
+            valid_time: used for pattern replacement
+        """
+        tarpath = valid_time.strftime(tarpath)
+        path = valid_time.strftime(path)
+        log.info("Reading %s:%s", tarpath, path)
+
+        with tarfile.open(tarpath, "r") as t:
+            f = t.extractfile(path)
+            yield read_odb_sql(f, self.odb_columns, self.odb_where)
+
+    def read_file(self, pattern: str, valid_time: TimePoint) -> Iterable[DataFrame]:
+        """
+        Read ODB2 data from a file, decompressing if required.
+
+        Paths can use strftime templates which will be replaced by valid_time
+        Paths can use shell globs
+        Recognised extensions for decompression are .gz, .bz2, .zst
+
+        Args:
+            pattern: path pattern to open
+            valid_time: used for pattern replacement
+        """
+        path = valid_time.strftime(pattern)
+        log.info("Reading %s", path)
+
+        for p in glob(path):
+            if p.endswith(".gz"):
+                with gzip.open(p) as f:
+                    yield read_odb_sql(f, self.odb_columns, self.odb_where)
+            elif p.endswith(".bz2"):
+                with bz2.open(p) as f:
+                    yield read_odb_sql(f, self.odb_columns, self.odb_where)
+            elif p.endswith(".zst"):
+                with zstd.open(p) as f:
+                    yield read_odb_sql(f, self.odb_columns, self.odb_where)
+            else:
+                with open(p, "rb") as f:
+                    yield read_odb_sql(f, self.odb_columns, self.odb_where)
+
     @abstractmethod
     def read_odb(self, valid_time: TimePoint) -> Iterable[DataFrame]:
-        """Read ODB2 data."""
+        """
+        Read ODB2 data.
+
+        Subclasses should implement this method to read ODB2 data for the given valid_time and return an iterable of DataFrames.
+        """
         raise NotImplementedError
 
-    def odb2ascii(self, output: TextIO, valid_times: Iterable[TimePoint]):
-        """Write all the observations to a MET ASCII file."""
+    def odb2ascii(self, output_pattern: str, valid_times: Iterable[TimePoint]):
+        """
+        Write all the observations to a MET ASCII file.
+
+        If output_pattern contains a strftime-style pattern then the valid time
+        will be used to replace the pattern.
+        """
         for t in valid_times:
+            output = t.strftime(output_pattern)
+
+            if output == "-":
+                out_context = nullcontext(sys.stdout)
+            else:
+                out_context = open(output, "wt")
+
             log.info("Processing %s", t)
-            for obs in self.read_odb(t):
-                ascii = odb2ascii_dataframe(obs)
-                write_ascii(ascii, output)
+            with out_context as f:
+                for obs in self.read_odb(t):
+                    ascii = odb2ascii_dataframe(obs)
+                    write_ascii(ascii, f)
 
 
 class PrepODB2Pattern(PrepODB2):
@@ -377,4 +451,4 @@ def read_odb(self, valid_time: TimePoint) -> Iterable[DataFrame]:
         Args:
             valid_time: Time to use in file patterns
         """
-        return read_file(self.pattern, valid_time)
+        return self.read_file(self.pattern, valid_time)
diff --git a/src/CSET/cset_workflow/app/metplus_prep_obs/bin/odb2/test_odb2.py b/src/CSET/cset_workflow/app/metplus_prep_obs/bin/odb2/test_odb2.py
index 1957ea60e..90e064e3b 100644
--- a/src/CSET/cset_workflow/app/metplus_prep_obs/bin/odb2/test_odb2.py
+++ b/src/CSET/cset_workflow/app/metplus_prep_obs/bin/odb2/test_odb2.py
@@ -1,16 +1,19 @@
 """Tests for ODB2 to MET ASCII conversion."""
 
 import io
+from unittest.mock import patch
 
 import numpy
 import pandas
 
 from .odb2 import (
     ASCII_COLUMNS,
+    PrepODB2Pattern,
     get_height,
     get_level,
     get_type,
     odb2ascii_dataframe,
+    read_odb_sql,
     write_ascii,
 )
 
@@ -157,3 +160,56 @@ def test_write_ascii():
     write_ascii(ascii, output)
     expect = "ADPSFC\tDUMMY\t20010101_0100\t10\t20\t30\tt2m\tNA\t0\tNA\t40\n"
     assert output.getvalue() == expect
+
+
+def test_read_odb():
+    """Test read_odb."""
+    with patch("subprocess.run") as mock_run:
+        mock_run.return_value.stdout = (
+            "name@varno\tvertco_type@body\tvertco_reference_1@body\n"
+        )
+        mock_run.return_value.returncode = 0
+        df = read_odb_sql(
+            io.BytesIO(), ["name@varno", "vertco_type@body", "vertco_reference_1@body"]
+        )
+        assert isinstance(df, pandas.DataFrame)
+        assert list(df.columns) == [
+            "name@varno",
+            "vertco_type@body",
+            "vertco_reference_1@body",
+        ]
+
+
+def test_PrepODB_read(tmp_path):
+    """Check the prepODB2 read_odb method returns a DataFrame with the expected columns."""
+    obs = pandas.DataFrame(
+        [
+            {
+                "reportype@hdr": 16001,
+                "report_status@hdr": 1,
+                "date@hdr": 20010101,
+                "time@hdr": 10000,
+                "datum_status@body": 1,
+                "varno@body": 39,
+                "statid@hdr": "DUMMY",
+                "lat@hdr": 10,
+                "lon@hdr": 20,
+                "stalt@hdr": 30,
+                "obsvalue@body": 40,
+                "vertco_type@body": 5,
+                "vertco_reference_1@body": 1,
+            },
+        ]
+    )
+
+    (tmp_path / "test.odb2").write_text("")
+    pattern = str(tmp_path / "test.odb2")
+
+    with patch("odb2.odb2.read_odb_sql") as mock_read_odb_sql:
+        mock_read_odb_sql.return_value = obs
+
+        prep = PrepODB2Pattern(pattern)
+        df = next(prep.read_odb(pandas.Timestamp("20010101T0100Z")))
+        assert isinstance(df, pandas.DataFrame)
+
+        assert df["reportype@hdr"].iloc[0] == 16001
diff --git a/src/CSET/cset_workflow/app/metplus_prep_obs/bin/prepBureauNCI.py b/src/CSET/cset_workflow/app/metplus_prep_obs/bin/prepBureauNCI.py
index 2c3e1a191..ecba51bbc 100755
--- a/src/CSET/cset_workflow/app/metplus_prep_obs/bin/prepBureauNCI.py
+++ b/src/CSET/cset_workflow/app/metplus_prep_obs/bin/prepBureauNCI.py
@@ -6,17 +6,16 @@
 Valid times can be either ISO timepoints or recurrences, and are used to replace any strftime patterns.
 Data is sourced from the mirror in the ig2 project, not all times are available.
 
-    ./prepODB2.py \
+    ./prepBureauNCI.py \
             --system access-c3-dn \
             --valid-time 20010101T0000Z \
             --valid-time R4/20010102T0000Z/PT6H \
-            --output obs.ascii
+            --output obs.%Y%m%dT%H%MZ.ascii
 """
 
 import argparse
 import logging
 import sys
-from contextlib import nullcontext
 
 from odb2 import valid_times_iterator
 from odb2.bom import BOM_SYSTEMS, PrepBomNci
@@ -54,15 +53,10 @@ def main(argv: list[str]):
         logging.basicConfig(level=logging.DEBUG)
     else:
         logging.basicConfig(level=logging.INFO)
-        sys.tracebacklimit = 0
 
-    if args.output == "-":
-        out_context = nullcontext(sys.stdout)
-    else:
-        out_context = open(args.output, "wt")
-
-    with out_context as output:
-        PrepBomNci(args.system).odb2ascii(output, valid_times_iterator(args.valid_time))
+    PrepBomNci(args.system).odb2ascii(
+        args.output, valid_times_iterator(args.valid_time)
+    )
 
 
 if __name__ == "__main__":
diff --git a/src/CSET/cset_workflow/app/metplus_prep_obs/bin/prepODB2.py b/src/CSET/cset_workflow/app/metplus_prep_obs/bin/prepODB2.py
index c021a261d..500ed02d7 100755
--- a/src/CSET/cset_workflow/app/metplus_prep_obs/bin/prepODB2.py
+++ b/src/CSET/cset_workflow/app/metplus_prep_obs/bin/prepODB2.py
@@ -9,13 +9,12 @@
     ./prepODB2.py /path/to/%Y/%m/%Y%m%dT%H%MZ/*.odb \
             --valid-time 20010101T0000Z \
             --valid-time R4/20010102T0000Z/PT6H \
-            --output obs.ascii
+            --output obs.%Y%m%dT%H%MZ.ascii
 """
 
 import argparse
 import logging
 import sys
-from contextlib import nullcontext
 
 from odb2.odb2 import PrepODB2Pattern, valid_times_iterator
 
@@ -71,16 +70,10 @@ def main(argv: list[str]):
         # Valid time unset, hopefully the pattern isn't using times
         args.valid_time = ["00010101T0000Z"]
 
-    if args.output == "-":
-        out_context = nullcontext(sys.stdout)
-    else:
-        out_context = open(args.output, "wt")
-
-    with out_context as output:
-        for pattern in args.file:
-            PrepODB2Pattern(pattern).odb2ascii(
-                output, valid_times_iterator(args.valid_time)
-            )
+    for pattern in args.file:
+        PrepODB2Pattern(pattern).odb2ascii(
+            args.output, valid_times_iterator(args.valid_time)
+        )
 
 
 if __name__ == "__main__":
diff --git a/src/CSET/cset_workflow/app/metplus_prep_obs/opt/rose-app-nci-gadi.conf b/src/CSET/cset_workflow/app/metplus_prep_obs/opt/rose-app-nci-gadi.conf
index 61375dd49..1fa93ef26 100644
--- a/src/CSET/cset_workflow/app/metplus_prep_obs/opt/rose-app-nci-gadi.conf
+++ b/src/CSET/cset_workflow/app/metplus_prep_obs/opt/rose-app-nci-gadi.conf
@@ -1,4 +1,4 @@
 [command]
 # Read in files from ig2
 default = mkdir -p "$METPLUS_OBS_DIR"
-        = app_env_wrapper prepBureauNCI.py --system "$METPLUS_OBS_SYSTEM" --valid-time "$OBS_TIMES" --output "$METPLUS_OBS_DIR/${CYLC_TASK_CYCLE_POINT}.ascii"
+        = app_env_wrapper prepBureauNCI.py --system "$METPLUS_OBS_SYSTEM" --valid-time "$OBS_TIMES" --output "$METPLUS_OBS_DIR/obs.%Y%m%dT%H%MZ.ascii"
diff --git a/src/CSET/cset_workflow/app/metplus_prep_obs/opt/rose-app-odb2.conf b/src/CSET/cset_workflow/app/metplus_prep_obs/opt/rose-app-odb2.conf
index a47fea382..7ad4f9f67 100644
--- a/src/CSET/cset_workflow/app/metplus_prep_obs/opt/rose-app-odb2.conf
+++ b/src/CSET/cset_workflow/app/metplus_prep_obs/opt/rose-app-odb2.conf
@@ -1,4 +1,4 @@
 [command]
 # Read in files from ODB2 files by providing a strftime pattern
 default = mkdir -p "$METPLUS_OBS_DIR"
-        = app_env_wrapper prepODB2.py --valid-time "$OBS_TIMES" --output "$METPLUS_OBS_DIR/${CYLC_TASK_CYCLE_POINT}.ascii" $CUSTOM_ODB2_PATTERN
+        = app_env_wrapper prepODB2.py --valid-time "$OBS_TIMES" --output "$METPLUS_OBS_DIR/obs.%Y%m%dT%H%MZ.ascii" $CUSTOM_ODB2_PATTERN
diff --git a/src/CSET/cset_workflow/bin/app_env_wrapper b/src/CSET/cset_workflow/bin/app_env_wrapper
index e67211101..a03dbaa26 100755
--- a/src/CSET/cset_workflow/bin/app_env_wrapper
+++ b/src/CSET/cset_workflow/bin/app_env_wrapper
@@ -11,7 +11,7 @@ set -euo pipefail
 if [[ $CSET_ENV_USE_MODULES == True ]]; then
   IFS_SAVE=$IFS
   IFS=' '
-  if [[ "$MODULES_PURGE" ]]; then
+  if [[ "$MODULES_PURGE" == True ]]; then
     module purge
   fi
   for module in $MODULES_LIST; do
diff --git a/src/CSET/cset_workflow/opt/rose-suite-nci-gadi.conf b/src/CSET/cset_workflow/opt/rose-suite-nci-gadi.conf
new file mode 100644
index 000000000..dede8b080
--- /dev/null
+++ b/src/CSET/cset_workflow/opt/rose-suite-nci-gadi.conf
@@ -0,0 +1,25 @@
+[template variables]
+SITE="nci-gadi"
+
+# Storage flags to add
+NCI_STORAGE=["gdata/dp9"]
+
+# Where to store output website (view from ARE virtual desktop)
+WEB_DIR="~/public_html/$CYLC_WORKFLOW_NAME"
+
+# Default module
+CSET_ENV_USE_MODULES = True
+CSET_ENV_SEPARATE_MET = False
+MODULES_PURGE = False
+MODULES_LIST = "/g/data/access/ngm/modules/cset/26.7.0"
+
+# # Paths to local checkouts of repositories
+# VERPY_DIR = "/path/to/verpy"
+# CSET_DIR = "/path/to/cset"
+
+# # Metplus information
+# # OBS_SYSTEM can be access_g{3,4}, access_c{3,4}_{ad,bn,dn,nq,ph,sy,vt} or custom
+# METPLUS_OBS_SYSTEM = "access_g4"
+#
+# # If OBS_SYSTEM is custom, what path should be read
+# CUSTOM_ODB_PATTERN = "/path/to/files/%Y%m%dT%H%MZ.odb2"
diff --git a/src/CSET/cset_workflow/site/nci-gadi.cylc b/src/CSET/cset_workflow/site/nci-gadi.cylc
index 543ef4ea5..44f7904b6 100644
--- a/src/CSET/cset_workflow/site/nci-gadi.cylc
+++ b/src/CSET/cset_workflow/site/nci-gadi.cylc
@@ -2,10 +2,14 @@
 
 # Site configuration for NCI Gadi
 #
+# Using the opt file 'nci-gadi' is recommended to ensure the CSET module is
+# loaded correctly
+#
 # Important rose-suite.conf settings:
 #   SITE = "nci-gadi"   # Enable the site
 #   PROJECT             # NCI project code
 #   VERPY_DIR           # Path to Verpy source code
+#   NCI_STORAGE         # List of NCI storage locations to use
 #   METPLUS_OBS_SYSTEM  # Where to source obs from
 #                       # Can be a Bureau forecast system e.g.
 #                       # 'access_c3_dn' or 'custom'
@@ -14,16 +18,19 @@
 #
 # Leave METPLUS_FCST_DIR and METPLUS_OBS_DIR unset
 
+{% set STORAGE = [
+    'scratch/'~PROJECT,
+    'gdata/'~PROJECT,
+    'gdata/access',
+    'gdata/hr22',
+] + (NCI_STORAGE | default([])) %}
+
 [runtime]
     [[root]]
         platform = gadi_background
-        init-script = """
-            module use /g/data/access/ngm/modules
-            module load cset/26.4.0
-            """
         [[[ environment ]]]
             PROJECT = {{ PROJECT }}
-            PYTHONPATH = "{{VERPY_DIR}}"
+            PYTHONPATH = {{VERPY_DIR}}{% if CSET_DIR is defined %}:{{CSET_DIR}}/src{% endif %}
 
 {% if RUN_METPLUS_GRID_STAT|default(False) or RUN_METPLUS_POINT_STAT|default(False) %}
     [[METPLUS]]
@@ -34,14 +41,14 @@
             -q          = normal
             -l ncpus    = 1
             -l mem      = 4gb
-            -l storage  = scratch/{{PROJECT}}+gdata/{{PROJECT}}+gdata/access+gdata/dp9+gdata/hr22+gdata/ig2+scratch/dx2
+            -l storage  = {{ STORAGE | join('+') }}+gdata/ig2
             -W umask    = 0022
         [[[ environment ]]]
             ANALYSIS_LENGTH = {{ANALYSIS_LENGTH}}
 
     [[metplus_prep_obs]]
         [[[ environment ]]]
-            OBS_TIMES = R{{ANALYSIS_LENGTH | duration_as('h') | int }}/$CYLC_TASK_CYCLE_POINT/PT1H
+            OBS_TIMES = R{{(ANALYSIS_LENGTH | duration_as('h') | int) + 1}}/$CYLC_TASK_CYCLE_POINT/PT1H
         {% if METPLUS_OBS_SYSTEM != "custom" %}
             # Forecast system to pull obs from (e.g. 'access_c3_dn')
             METPLUS_OBS_SYSTEM = {{METPLUS_OBS_SYSTEM}}
@@ -60,7 +67,7 @@
             -q          = normal
             -l ncpus    = 48
             -l mem      = 180gb
-            -l storage  = scratch/{{PROJECT}}+gdata/{{PROJECT}}+gdata/access+gdata/dp9+gdata/hr22+gdata/xp65+scratch/dx2
+            -l storage  = {{ STORAGE | join('+') }}
             -W umask    = 0022
         [[[ environment ]]]
             BUNCH_POOL_SIZE = $PBS_NCPUS
@@ -73,7 +80,7 @@
             -q          = normal
             -l ncpus    = 48
             -l mem      = 180gb
-            -l storage  = scratch/{{PROJECT}}+gdata/{{PROJECT}}+gdata/access+gdata/dp9+gdata/hr22+gdata/xp65+scratch/dx2
+            -l storage  = {{ STORAGE | join('+') }}
             -W umask    = 0022
         [[[ environment ]]]
             BUNCH_POOL_SIZE = $PBS_NCPUS