Should I transplant this?

Hey guys so I started this photo ethos member berry in August into 1gallon pot expecting it to be a little nug plant maybe a couple inches tall. But it got a little bigger than I expected and it's like 2 and a half weeks into flower now. Should I transplant it into bigger pot or just let it get rootbound and harvest what I can.

It's already in flower you definitely don't need to transplant just keep doing what your doing.