I just moved them to 1L plastic buckets (drilled some holes in the bottoms, of course) which I had handy. I put them pretty deep into the soil. Unfortunately the taproots were already sticking out of the bottoms of the plugs and bending sideways. I put a fan far away from them so that they wiggle just a little bit.
It's just the interim as I'm moving them into the tent and under the lamp on a 18/6 timer tonight.
I tried to be as gentle as possible, but I'm aware it may be too late for those babies. Keeping my fingers crossed. Oh well, all rookie mistakes.
By the way, what caused the stems to be this long?