AR 2-16-11-III does make it clear that the fair catch team may NOT elect to put the ball in play by snap, then change their mind after the ball is ready for play. After the ball is ready for play for first down, they are locked in to playing a scrimmage series.
(In NFHS, they can change to a FCK after a foul by either team - pre-snap or live ball - when first down is continued/repeated. Glad the NCAA nixed that option.)
But, still don’t know what to do about the kicker getting blocked before he has advanced 5-yards, or ball has touched the ground or a player/official. I hope they figure out that they need to give the kicker this protection on FCKs, and then treat the rest of the down as a scrimmage kick.