** HELP Por Favor ** Possible root bound issue?

Hi folks, I've got 5 Spacebombs that I believe are/or have become rootbound. They are in 20 gallon smart pots, and I'm in my third week of flower. The leaves are constantly drooping, too. Would it be wise to transplant them into a 32 gallon pot considering I'm 3 weeks into bloom? If so, any recommendations on how to safely do this? Thanks RIU

I can add pictures tonight when the lights come on.