No problem letting them go as long as they want in veg but since you are showing preflower the plant is telling you it is ready.
That makes it your decision 100% on when to flower them. If the clone provided said the momma was short then 14-16" sounds about right to start flowering now. With your 5' height you won't have any problems keeping it manageable. I'd bet you end up at about 32-36" at finish give or take a couple of inches.
That makes it your decision 100% on when to flower them. If the clone provided said the momma was short then 14-16" sounds about right to start flowering now. With your 5' height you won't have any problems keeping it manageable. I'd bet you end up at about 32-36" at finish give or take a couple of inches.