Yeah it’s easy. At the start, at least.
You mentioned you also have previous experience already learning Japanese, so you’re likely going over material you already know, basically as a refresher, so I can imagine that will also be pretty simple to grasp.
You’ll start running into problems if you consistently learn new, difficult content while maintaining these numbers. It really only takes a couple days of grammar points that really stump you to completely throw off your numbers if you’re not careful.
As long as you’re still managing your numbers and your study time isn’t eating into your free time too much, feel free to keep working at this pace. Be aware that once you reach content that you struggle with, you may slow down or completely stop being able to take in new material until you manage to comprehend what’s already on your plate.
Remember that you don’t want to be spending 2-4 hours a day “traditionally studying”. 30 minutes to an hour of book study is around what I recommend generally, followed by as much good immersion as you can manage in that day (reading Japanese literature like manga, ln, actual books, watching shows/anime [NO EN SUBTITLES], playing games/vns in Japanese, speaking to Japanese people/listening practice, etc.) without interfering with your day-to-day life.
SRS is a good tool for introducing concepts and vocabulary, but the best way to learn something is to encounter it “in the wild” while immersing after doing a preliminary study, as it’ll be fresh in your mind.
Be careful with your learning, remember that it’s a lifestyle choice and not a race. If you notice things are slowing down, decrease your numbers for new content and focus on what you’re learning now to have a good foundation of knowledge for the future.