Don't flower anything over 3 ft and you should be fine...that depends on how much you train the plants as well...but some strains can get 3x the size they started flowering...So maybe nothing over 2 ft...I have very little upwards room because i use a 5 ft tent but I have my lights and filter sitting right there...anyway, if you train the plant early in veg you can get more bud, but less height...it is easy, but you pretty much need to train indoor plants, if not you are hurting the yield you could have had, ya know?Would you advise to grow in height before the the switch? Just want a rough estimate, ive got a 6ft room and just not sure how much they grow in height after the switch! Thanks in advance! Hope ur all good!