If you’re not doing new lessons, you’ll stay at your current level. You level when you get a certain number of the new kanji to guru level - which means you have to learn it and review it correctly a number of times.
My leveling speed was atrocious for a while because I was so focused on just doing reviews and didn’t do any new lessons for days.
You’re always going to have reviews (unless you get everything to Enlighted, in which case you’ll have nothing to do). 100 reviews a day is not crazy. Just focus on what you can do, if that’s not clearing out your reviews to zero, that’s normal. Try to add even 5-10 new lessons every day. You probably won’t see that crazy of an increase in the number of reviews.
