Depends on what your tent can handle and the stretch could go out of control brother ..your humidity will go beyond 60% when flower hits and the walls will have branches touching for sure .. I would flip them pretty soon my self ,hard to see how they look with led lighting .. because of the variables I would flip them soon brother . Cheers
In my opinion you don't need to fill your area first. It's better if the plants have some space to go in to flowering. I made this mistake, and the plants growed in to each other and there wasn't very much airflow between the ladies. Good luck