The default time is the mid-point for the slot between other 2 items.
So for your example if you select + above the most recent watch the default datetime will be mid-point between Now and most recent watch. You can then click Edit icon to fine tune it.
Can we have a way to disable this slot picker, I mostly log my watches in bulk, so this new screen is just an extra screen to bypass as the date/time it offers is wildy wrong
I just want to be able to enter a date/time of my watches