I think most go to a 28q tub before moving them up to a 41q. It's going to depend on the current size of your animal though. I tend to keep hatchlings in 6q tubs till they settle in and are eating well, I usually move them to the 28's when they hit 100 grams. I don't typically move them to 41's till they go over 1000 grams.
Yeah definitely get a tweener tub. That jump from 10 to 41 is quite large and may stress out your snake. When you go up to 41 definitely throw in a 2nd hide for a while. It will help.