Expressions like 5d, 10d, 1m are properly parsed in an oo3 column as long as the inspector shows it to be of type Duration rather than type Rich Text.

If the column is currently Rich Text, changing its type to Duration should work fine, and result in automatic type conversion, as long as the duration strings are all well-formed, conforming to the patterns known to oo3.

You can then map an oo3 duration column to the OF duration field during the drag and drop process, but you can't really map duration data to date fields ... (if that is indeed what you meant ?) Duration expressions just specify a total number of minutes - they don't correspond to particular calendar dates ...

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