I’m actually a complete OHM beginner, so I would have to defer to @jeffmeyer and @Minh_Nguyen about this! Here’s a recent discussion that touches on the topic at least: On what date does end_date end?
It seems to me that when digitizing from maps like this, it would be really useful to have something like an “exists_on” date, because all you can often glean from the maps is that a feature existed at a certain point in time… Anyway, a good discussion topic for sure.