Hi Melinda,
in deed, in general you shouldn’t enter any dates if they aren’t really binding.
Planing with work (or duration) and dependencies lets your planing flexible and you can easily adjust it in case needed in the future,
If you need to be warned when a specific date is somehow not working, you should enter a precise date constrain. Merlin will push the start (or end) to a time point the resource works.
If the date constrain really applies, you need to fix it in addition.
So you may first use the 'precise date’. If this produces a warning, you can fix the date to make sure your resource gets planned as you originally require.
Best regards, Vicky