I'd be particularly wary of inferring anything from the EXIF data, especially the time.
We could (should!) store the date/time anyway, and slap a "source:EXIF" (or the like) qualifier on it.
If there is a "manual" time (e.g. written in the template), that could become the "preferred" time statement.
One would thus, by default, get the manual time, or EXIF time if no manual available. Or, one could ask specifically for either. Even if just to see how reliable EXIF time is in practice...