With installing a new offense, your priority should be giving your starter as many quality reps as possible and preparing your backup with whatever reps are left over. That's not what they're doing. Both guys continue to split time.

Yes, you need to prepare your backup, but not at the expense of getting the starter fully ready in a new offense. That they continue to split time suggests it really still is undecided. They might be leaning one way or the other, but they are not practicing like it is decided.