Full time job-human here!
How many panels I can draw really depends on the artwork, and drawing is only half the battle - writing and coloring also take up a lot of time. I would average it at about 5 panels if I can work for a couple hours after coming home from work, feeding the dogs and myself.
And no, I don't have other hobbies. I stay away from games purposefully, even from books (unless I can listen to them), or TV shows that require my full attention. I keep my weekends and vacations empty in order to draw. If friends visit, we usually draw together.
This may sound awful for many, but I enjoy drawing. It is a hobby and relaxing to me. If this isn't the case for you, a huge project like a webcomic can quickly turn into a burden. And I also can get tired of it.
Depending on how dedicated you are, you will either work through it or take a break (maybe even give up on it). And that's fine - you are here because you want to anyways.