I also did 3x~100 kanji in the last 3 days, but the only reason i was able to do it, was because ive spent my whole days on it. It's already 5 months for me, i had too many breaks between reviews and im motivated to get it done within next week. Free days are really a blessing, but i still think that 20-30 new kanji each day would've been better, i get a lot of wrong answers where i mistake some kanji for another ones . I'll know all the 2042 kanji faster, but my knowledge won't be as solid as if it would've been when adding less kanji and kept doing it like i should've been. Also, im pretty sure i wouldn't be able to add 100 kanji from the beggining, even with 24/7 free time.