Roots outgrew pot

I'm sure the simple answer is to just transplant, but it just caught me off guard when i shook off the runoff towel and found a clump of severed roots from my rank#1 ( sorta now #2) of my sea of green of future mothers. I transplanted her from a red solo a couple weeks ago and she's now 40 days old and has foot long roots jeezus, i could transplant up into a 5 gallon now but i think ill wait till tomorrow

What is a "runoff towel?" Don't you use a saucer? It's common for roots to poke out the runoff holes. Basically they are "air pruned". If you have a wet towel sitting beneath the container, that's like an invitation to root. And then you break the roots off when you remove the towel.