You could always learn the solutions once and put them into a set of Anki flashcards, so that you occasionally get reminded to practice them just before you forget them. You really don't have to keep repeating the 3 months "from scratch" experience. That's what I have done, pretty badly to be frank, and the prep time is now closer to 2 weeks.

Compared to many other industries where people are required to go get expensive and time consuming "continuing education", I don't think keeping a timed flashcard deck of maybe a couple hundred items total in rotation is all that onerous.