one more thought - -
some players commit without any official visit at all. If your son likes the school & the deal is "generous" as you say it may simply be the opportunity for son & parents to meet the coaches & tour the school on their dime before the handshake sealing the deal.
re stalling for more time - - the dead period ends Nov 9, signing ends Nov 15 so there is a small window there before opting for a late signing period deal - which, if the visit goes well it would seem pretty likely that their interest would continue into spring - but nothing's a sure thing so maybe you'd want to just ask & note their reaction.
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