How Long For GDP To Start Flower Stage

Hi All, First grow and starting with 6 plants. Seeds sprouted within 2 days BIG Props to ILGW!! Anyway I’m going to grow a few out side so I guess they will flower when they are ready based on daylight. My question is how long before I transition the indoor grow to the 12 on 12 off? I have them in a 48x48x80 tent with a 1200W LED (Not sure if I need to add a second?). Right now I have them on an 18 on 6 off schedule. The plants are looking really happy and are growing great. Or at least the look good to me. I’m a big super hot pepper grower and these are out pacing them. Anyway I started these near the 3rd week of April so they have been growing about 6 weeks now. I’m guessing I still have a ways to go just not sure how much time I should plan on? Thanks in advance for any feedback.

I have 4 northern lights I just switched to 12/12 on 6/1. They had their cotyledon leaves on 4/2 which is when I started counting grow days. It was day 55 when I flipped. Because of training and topping the tallest was only 11".

Red circle indicating sexually mature enough to flip.

Exactly. They will throw a pistil or two when they are ready to let u know they are mature. But whenever ur ready 12/12 will flip them for ya. Typically i flip when they are half intended finish size. They will double in growth easily after the light change. So plan accordingly.