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'IMAGE_'yyyyMMdd_HHmmss'.jpg' This will overrule the forecast time stored in the file, some grid formats don't contain the forecast time at all, so for these files the pattern is required. Put the literal parts of the pattern between single quotes. When the file name also contains non forecast date times. Put this parts between ' and use ? wildcard. All forecast with the same forecast time belong to the same forecast.
When filename starts with the pattern do not use quotes in at the start: yyyyMMdd'_bla.nc'fileNameLocationIdPattern
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