Just keep it light so you can continue to practice your back squat with perfect form. As soon as the form breaks down, you need to stop. However, if you go lighter you should be able to more reps. This is a good way to keep developing your technique as well as help build the muscles you need, as the weak muscles will fatigue first. But again, the more you practice with perfect form the faster the weak points will correct themselves. Once the weakness is corrected and your form improves, then you can start upping the weight. You obviously don't want to be doing sets of 10 forever if your goal is limit strength. But its not a bad idea for off season or bodybuilding work when you are far from a competition.
If you're squatting 2x a week, you might try something like:
Front squat to heavy triple
Back squat 3-5 sets of 5-10 with good form
Back squat to heavy triple with perfect form (if form breaks it's a miss)
Front squat for 3-5 sets of 4-8 reps