post some pics
they will continue to stretch for another 2-3 weeks they could grow another 1-2 ft in this time
not much you can do really, you could put them back on a veg cycle, but this will delay things for about 3-4 weeks
how long did you veg them
are they indica ?
is all your space filled ?
you could start some more plants now and get them in the flower room asap along side what you have now, and do a perpetual kind of thing have 2 harvest a month or so apart, that would help you get more yield in the quickest time frame
peace