Sounds like a fun challenge!
Have you tried something like this?
PS: so for now this is my log, I’ll be updating this top comment every new update.
grammar is different from vocab where grammar has conjugation rules, nuances, politeness levels. Things like this. Trying to remember that may grammar points in 2 months is definitely possible it’s just that your review per day might be unnecessarily high and you might get frustrated as it’s difficult to have a high retention rate which a large amount of information so quickly.
It’s about 522 grammar points and in 2 months that’s 8.7 grammar points per day. It’s possible, as anything is. However i’d say it’s better to take it slow with 3 a day or 5 a day. Higher retention and you can spend more time with each point learning the nuances between other similar grammar points instead of just bashing the english translation in your head.
8 a day is possible ofc. if you decide to do that, i would read on the side as well so you can get more exposure to what you are studying and increase retention
edit: i’m just a random person on the internet so who cares what i say and do what makes you happy
Such a chill response I love it)
Everyone is so kind in this community!
522 units * 10 reviews (on avg per unit) should be 5220 + some amount of ghosts (4 per unit is ok assumption?) so let is be 10000 - 15000 cards in 2 months at most, and it will 170 - 250 reviews per day -_-, I think it’s a lot considering rereading a grammar point after failing something. Should take at least 6 concentrated hours? I think I need to try to understand but I don’t have that much time because I’m learning kanji and words
i did n5 and n4 in one month and would recommend it to anyone thats willing to spend like 2 hours a day on it. i would say by the time you finish n3, you would probably be spending 3+ hours on it daily. if you realize that and are cool with it. i say go for it.
by the end of the month, i was doing about 250 reviews, so i think an estimate of an overall 300 ish reviews is a good estimate maybe. it takes a lot of time, but you should be able to do it. i also feel it was the most productive month of japanese learning because i learned so much. you will go from understanding pretty much nothing you read to understanding a lot of sentences (assuming you have decent vocab).
I would just do 1 study session in the morning where you learn all of your new grammar and do your reviews, then 1 at night where you dont learn any new grammar and just clear out your reviews before you go to bed.
Wow, that is less than I assumed, thanks!
Not sure that it will be the same for me but will see!
3 hours/day is fine with me because I have a lot of free time.
But have some other questions if you don’t mind answering them!
Have you practiced conjugations (all types) outside of your main reviews? For example in cram or just on the paper to get them?
It’s a bit unfortunate that there are no full exercise patch after each lesson but we have what we have and its cool.
Where in grammar people with levels of xp 10, 20, … 70 … ? Just curious)
i didnt practice them outside of bunpro reviews. I was originally getting them wrong a lot because i was just trying to grind them into my head, but eventually you realize that they all follow pretty similar patterns and can break them into various categories
i found that just doing the reviews was enough to teach me the general patterns of how they are conjugated.
for the levels question, im level 71 and finished n2 grammar. i think it will be different based on what they use bunpro for. I only use it for grammar, but some people use it for vocab to so their levels might be a little higher. I think i was around 35-40 ish when i finished n4, so take that for what you will
Thanks a lot!
I think I’m gona include this “grammar grinding” to my daily routine!
Nah, I have one more question)
Are topics getting larger&longer todo deeper you go?
Or they are designed the way to be standard size on average and aren’t growing to much?
i find that the n5 and n4 topics are actually the biggest. the conjugations are the hardest to learn because you have to remember all the little details, but later on the grammar points are a lot shorter and like vocab.
Worst idea i’ve ever heard of
i did 9 points a day from n5 to n3 and then because n2 and n1 were much easier to learn i calmed down a bit and went down to 6. Best choice of my life. If you can’t manage it though please lower the amount so you don’t get discouraged
I started Bunpro on June 7th. I put on Mastered around 81 items, before that I followed the Genki Videos by Tokini Andy and read most of Genki 1 so all the particles etc were already quite known.
Every day in June, I did around 6-9 new items for the first half of the month, then I went up to 12-16 on some days for the last part of the month. I So basically, I had the 126-81=45 items of N5 and ~177 N4 points in my review log on July 10th the day I went to Japan for 20 days. So it was well worth it to have a bit of extra fresh understanding 
To be honest, I don’t regret that at all. I think the only thing to keep in mind is to take the minimum amount of “complex” grammar point a the same time. For example, the そう、そうだ、ようだ… or all the honorific form caused my accuracy to drop from 80% to 60%.
So what I was sometimes doing is taking New Items “from further ahead”, but with items that were extremely easy, things like particles like のに “in order to”, etc etc.
But at the same time, learning those in vacuum is maybe not as good as learning them with real content to put them in your brain for the long run. FSRS is good to do the minimum amount of work to retain a maximum amount of flash cards, but those flash cards sometimes can give you a false sense of confidence. So I’d definitely make sure you don’t do that by sacrificing all the normal native input you’d get elsewhere.
But my opinion is, if you have time, there’s no problem doing more, as long as you’re not burning out. But some of us are able to study/practice/learn for long period, every day, without burning out. If it’s your case, why not ? As long as you don’t sacrifice everything else
For Anki, when I started japanese 6 months ago, I went up to 3-3.5h of reviews per day. It was exhausting, but the amount of vocab I learnt back then is tremendous compared to what I learn now with my 30min. Even if a lot of people told me it was bad to do so much Anki, there’s a lot of Kanji I just recognize now just because I spend a lot of times memorizing them in a vacuum. It’s just that if you only do that, then you’ll basically master all vocab and grammar but won’t still be able to understand/express anything confidently. So do a bit of everything, but as much as you want
That’s a nice approach with “taking from next topics” I’ll definitely think about it!
About Anki it is true, I was learning kanji 4 - 4.5 hours for last 11 days (80/day) so now I have like, 760 of them (math isn’t matching because I missed some in the process) from this week I lower it to 40, and wow, today felt sooo good)
Also added some words learning because 70 words for 760 kanji is not ok 
I think I’ll do 8 topics/day and after I learn “Heisig’s kanji” I’ll increase it by a bit
Anyway thanks for sharing I appreciate it!
i dont mean to backseat your learning, but i think that vocab could use the time more than the grammar. honestly speaking, i think that it would be better to go a little slower on grammar and spend more time on finishing RTK/adding vocab. theres not really any point in knowing n3 grammar if you dont know 100 words. thats a huge bottleneck.
but if you start learning more words, then feel free to learn as much grammar as you want. 80 a day is crazy lol thats awesome for rtk, i did like 20. just know that you will be severely limited by you vocab once you finish n3 two months from now.
I think that maybe finishing rtk, 1500+ vocab words, and n4 finished might be a more balanced goal (assuming you keep the crazy pace youre at, this would be a crazy amount of work for two months lol). Then youll actually be able to read stuff and understand it (although youll still be using a dictionary a lot). if you do decide to slow down, i would just change the goal to like 1k vocab or something. i found that n5 and n4 were the most massively impactful grammar points, after that its better to focus on vocab until you get a good base.
although its not the end of the world if you just keep your original goal. its just a matter of when you learn it, its all stuff youd be learning eventually anyways
+1 for this. On the assumption that someone is planning on speedrunning beginner material no matter what then the idea is to reach a point where one can learn from native input as soon as possible (at the cost of having a weaker grasp of the material that was speedran) so keeping a balance between grammar and vocab is important.
And +1 for this. Even if you speedrun some stuff with SRS at the start it will still take a similar amount of time to learn Japanese on an absolute scale. Maybe you’ll pick up a tiny bit of momentum from efficiency however more often than not people burn out or have to retread ground when following this kind of plan. Basically speedrunning beginner SRS material isn’t a shortcut in itself. You’ve still got to do the rest of the work.
As I often say on this forum, the main reason people fail to learn Japanese is that they simply quit. Even if you’re fast it still takes years. The most important thing is to just keep going. Genuinely good luck as I love seeing people speedrun stuff or achieve big study goals as it is very inspirational. Please update if you manage it!
Definitely a good plan 
I think 40 kanji + 6 grammar point + 30 words (I hope to reach the point where they start sticking in a few weeks) and on the third month I can concentrate on vocab to get it to 4000 (what I think is enough to watch most YouTube with no dictionary).
Thanks a lot for help and kind words!
Thanks a lot!
I’ll try not to burnout and keep learning)
First time in history of my speedruns I made an “anti burnout” workout with running and yoga and good time management so I hope this will help me to stay on track at least until I can consume authentic material!
By the time I started Bunpro I was L20 on Wanikani and had studied all of N5 and 1/4 of N4 using genki 1 and 2.
120 days later doing 5 points a day I’m now just about to finish N2 (13 points left) .
I’ve had on average 70-80 grammar reviews a day with about 30 extra vocab which i’ve added due to seeing more that are unknown the farther into N2 I go.
Having to do high review counts in one day is tough, sometimes I’m rendered unable to do anything else other than Bunpro 5 grammar points 100 reviews, Wanikani 30 lessons 200-300 reviews.
Still managble. Dunno if I’d be able to do more than 5 grammar points and still retain everything.
4 months and I’ve done All of N4 N3 N2. That’s already a blistering fast pace. Is there really any need to go faster?
I’ll echo what some others have said, in that it’s best to have a balanced approach if you really want it to stick. I made the mistake of just binging grammar years ago and got to a point of having most of it up to N3 understood, but I could do nothing with it as I had no vocabulary. And because I couldn’t really use it, it slowly got forgotten again.
Years later, after my immediate comfortable grammar probably dropped down to an N4.8, and during the COVID lockdown I also binged Remembering The Kanji 1, and did the whole thing in just over a month, but again, because my vocabulary was so weak and I never learned the readings for them, it again left me basically deaf and mute, although I could get the gist of simple written sentences from knowing the rough meaning of the Kanji. Cut to a year or so later and maybe my Kanji recognition had down to around 40-50%, exactly because I simply wasn’t using them or practicing them any more, because I’d “done” it already, and then did nothing with it.
It wasn’t all for nothing, as re-learning something and it ringing a bell beats a completely fresh start, but I don’t think you can just master spinning one plate, and then move on to another singular column of the language to master that after. I think they all need to be brought up together, bit by bit. You need to keep spinning all the plates faster bit by bit, hopping around to keep them all roughly in line.
So could you learn N5/4/3 grammar points in two months? Absolutely if you have the time and grit. They might seem pretty hollow if all the rest of the words around the specific grammar points seem alien, though. It won’t really connect in the same way it would if the new grammar was the only bit naturally had to focus on.
And having achieved that anyway, will it be useful with limited grammar and Kanji knowledge? Not really. Unless you immediately start adding flesh to those bones with the same energy, all WHILE revisiting those grammar points every day to keep them burned in.
So you may as well just learn all aspects in tandem, the same way humans tend to learn languages.
BUT, if you do just fancy binging and hyper-focusing on one aspect for a fun challenge, I’d recommend doing it with Remembering The Kanji 1, while also including the On’yomi readings in your mental stories/images if you can. And then don’t do what I did and take a break to recover and forget 50% of it within a year. Keep at it.
Making sentences is the only way to truly learn, remember grammar, and gain the ability to truly use it. Just doing these reviews and reading premade sentences is nothing. Because what about when you have to talk. always keep this in mind when learning grammar.