lowryder 2 question

So I have 1 lr2 plant after it germed it pretty much died I kept it in the system for heck of it. The thing came back growing very strong just looks like it was topped as a seedling anyway i need to start new plants and it is taking space I veg at 18/6 but I dont have anywhere to start my new ones. Can i put it in my flower room 12/12? Will it still bud nicely?

Also when should I start the flowering nutes it has one preflower?