Hey there, I have sorta a weird approach to my buffer that I thought I might pop in and share.
So for my comic Skeletons in the Closet (cough..) I have a 10 page buffer of sequential finished pages, that's about 2 months for me because I'm uploading at a page a week.
BuuuUuut I have another 20ish pages that are in a state of work-in-progress, because I work on multiple pages in a week, all of these pages are in different stages of production as well, (for example lets say pages 18-20 are almost finished and just need some cleanup while pages 15-17 are just thumbnails/rough pencils and pages 10-14 have rough flat colors.) because of this, I can always find something to do depending on how much energy/time I have, (for example If im watching a show I can do some flat coloring because that doesn't take much focus, but if I've got a lot of time to focus I can finish up a page and do a lot of detail work.) These pages last me for the rest of the year.
I feel like this method is sorta a hybrid of the two approaches that @punkarsenic was talking about, it has the pros of keeping you on your toes because you only have a short backlog of finished pages, but it also lets you have a bit more control as far as planning your story goes (assuming you arent working from a complete script like I am) As an additional bonus, this method keeps the artwork across a long stretch of pages more consistent, so you wont feel like you're not able to show your best work (or at least not as badly)
I'd reccomend giving it a shot, and if you dont like it you can easly phase into either a long buffer or a short buffer, whichever you think you'd be more comfortorable with.
Hopefully that made enough sense? lemme know if I can explain anything better.