Look at my last post please

Transplanting isn't always about there being no more space for roots. Transplanting is known to help sick plants, I've used this many times myself. Fresh medium does wonders. You don't always have to go to final pot size, I go from solo to my final 3-5 gallon size but you can have sizes in between if you would like. Transplanting is also about how much water the medium can hold, as your plant grows the water uptake increases and having a bigger pot with more medium will hold more water which will reduce the need to water more often. Your plant is at the stage it's going to start growing faster, having it established and healthy in its final pot in preparation for topping, training, etc is important to help reduce stress during those training periods.

Roots do not need to be a tangled mass (rootbound) to cause problems, as soon as the plant "senses" that its roots are running out of room, as in a solo cup, hormonal changes will signal the plan to slow down, leading to stunted plants.........the bonsai principle. This is why myself and others reccommended transplanting. No doubt now that they are in bigger containers, growth should accelerate rapidly.

When it is exaclty "rootbound" is up for debate a bit. Obviously, at minimum it is the point at which the plant has issues with nutrient/water uptake due to root mass suffocating itself. Some methods are more robust against it than others... e.g. with soilless nutes, i can make a solo cup crack open due to mass of roots inside before leaf symptoms are too severe. In soil you will run into more severe issues long before that point. It's something that will evolve over time and get worse and not like an on/off switch. It was probably a good idea to pot up. You don't want the roots to be wrapped around 50 times causing visible symptoms on your plant. Roots wrapped around the bottom a handful of times is fine... can always jostle it loose and spread it out when potting-up... don't be to anal about that, though. ripping roots isn't worth it, but if it's already fairly loose spreading it out is fine. you definitely want 'enough' root growth that the rootball does not disintegrate from gental handling. Moisture and roots should hold it together during the process. if that was the case, then all is well. can't look at your post, because GD is tweaking out again... basic functions randomly not working.