Autos showing sex for 1 month but have not started to flower

I have 3 female Sensi Seeds Indica Ruderails all about 15 to 18 inches tall in 2 gallon nursrey pots with soil. My problem is I started them on Dec. 1st and all 3 sprouted on the 3rd, they have grown fast and look very healthy but as soon as they started to show there sex they seemed to come to a standstill as growth and flowering is concerned. They have been showing there sex for 29 days now with no signs of starting to flower. I have them under a 6 blub 4foot T5 HO light with a schedual of 20 on 4 off and am giving them nutes as according to shcedual. The room running quite cool for about 2 weeks, 65F to 70F as we had cold weather where i am at and could not get the room tem up to where i need it. I have now gotten the room temp under control for the last 2 weeks but the plants still have not done anything. I was wondering if anyone else has had these kind of problems and what i can do to give them a push into flowering.

hell switch em to 12/12 and see if you can get em to flip.i have never had the problem myself but this is what i would probably do if it where me.ive herd of it before and generally switching to 12/12 is the answer.

If my math is correct those plants are about 60 days old. They aren't autoflowers. You should have had harvestable (~) buds by now.

Yeah that is what I planned on doing but right now i have a photo peroid in there with them and cannot change the light cycle untill i am done LST it in Veg. I was more just wondering if anyone else had these same issues.

they are auto seeds, i grew 5 out before these with 3 females and they finished right around 80 to 85 days.

If you have to switch them to 12/12 to get buds I wouldn't consider them stable autoflowers. Perhaps you got a bad batch.