I am going to wait, and just stick with 15.10 for the time being; but a family member wishes to get 16.04 going now.
So then, her question orbits the notion of what the update process will entail up until April - and then (most importantly) once 16.04: Stable is released.
She, primarily, wants verify that there would be no reason for her to do a fresh install of 16.04 again, in April, if she puts 16.04 in today (there is the concern that new features, put in between now & Stable, will be left out of her environment without doing a fresh install at that time).
Thanks!