I have class in weekdays, so I only write in weekend in microsoft word using laptop, I can't use my phone for writing because my phone has some severe troubles and I haven't had any chance to buy a new one.
When I first started the novel, I was in holiday (around three-four months ago), so I have quite a stockpile by now. However, those chapters that I write still have a lot of grammar problems. I checked them again before copying them into the inkstone and set the timer (i use timer to maintain stable release since I can't stay online too much). In my case, I'm not working yet, so I still have time after college.
My chapter is not that long, only around 900-1200 words each chapter (mostly only around 1000 tho). My release rate is around 5 chapters each week and sometimes I give bonus chapters for several reason :)
As of now I don't have much leisure time, even the novels that I want to read for ages have been put on halt sadly because my schedule didn't let me have too much time for other activities.
If your schedule is so tight, you might want to change the release schedule or halt first to create a stockpile. Well, I guess this is all from me. Hope it helps.