I started with 30 pages of buffer, and I still have 25 after removing 3 pages because they weren't really important to the story, taking a week off of drawing once for family reasons, and the natural 'buffer decay' of drawing four pages a month... but sometimes having 5 updates a month.
Either way, if I stopped drawing right now, and continued only posting 1 page a week as I have been doing (this MIGHT change temporarily for an upcoming fight scene), I could technically keep posting until February 4th before I ran out of pages.
Has having such a large buffer come in handy? Not yet, but I made it this large as a 'what if' fallback. What if I have to move? What if I get sick or injure my hand? What if I'm dealing with something really stressful for a long period of time (family illness, etc) and just CAN'T make myself draw? You know, mid-to-long term problems that would make it really hard to draw consistently. I imagine if I ever have to deal with something like that, my huge buffer will come in VERY handy.