I can say the fatigue hit me hard in the last week. I started this past Sunday morning with 279 Lessons and 348 Reviews, because I just wasn’t keeping up and feeling motivation slipping. I had to take a step back, and be honest with myself about trying to maintain the pace I was going at (7-9 days per level), and realize that clearly, it wasn’t doing me any good. I’ve managed to clear out that review pile and am slowly chipping away at those lessons.
I suggest the self-study script if you can. Instead of piling on new stuff, I’ve been drilling a lot of the stuff that I kept stumbling on, as that was a major source of my frustration (and why my review pile wasn’t shrinking) of repeatedly getting things wrong (to transmit vs to be transmitted, and similar mistakes)
I also suggest a reorder script (used carefully). That way you can still do lessons for new radicals/kanji without feel like you need to tear through the huge block of vocab to get to it. You can then chip away at the new vocabulary as you have time and energy to work on those. I also tackle a one session of kanji (5 new ones) every hour, instead of trying to do all the new ones that unlock in one go.
As nice is it is to see progress quickly, it’s the journey, not the destination that matters!