More suggestions? Pro or cons opinions?
I'd just save one timestamp, ie TAI64 or as java does miliseconds since epoch, in a single, new field. saving the timestamp in two fields seems messy.
miliseconds since epoch is probably preferable, since it can be converted to human readable dates by the database server.
then have a flag that may be enabled, which additionally saves the time in the current format (with less precision) -- for backward compatability.
but a change like this i'd save for a 5.0 release.
kind regards Thilo
Cheers, Daniel