Help! Plant sexing in veg!!

I have a 3 blue hammer x killa queen plants that are in veg. Had them for 6 weeks under 24/0 and switched them two weeks ago to 20/4 wanting more roots and 1 is showing preflowers. I'm not ready to flower her. I put the 3 back under 24/0 last night because I don't want to flower yet. Can I continue to veg with preflowers showing?? Can I put them on 20/4 or keep them on 24/0 and hope it stops flowering?? Please help.

Yes. And just keep at 24.

Sent from my SCH-I545

Every time I run c-99 it shows preflowers the 5th week of veg. It isn't a problem.

I'd rather not keep them under 24/0. I really think the plant shows better growth under 20/4 but I don't want the flowers to develop. Is 24/0 the only solution?