I'd worry with an update schedule like that you'd risk readers forgetting about your series inbetween post. Once a week, I feel, is barely enough already to keep my comic fresh in the reader's memory. With a month between updates, even if it's a chunk of story per update, there's a risk of losing your place in the story, forgetting what's going on, who's that character?, why am I following this comic? That'd be my concern anyways.
I really liked being able to update 2x's a week. That felt like a really good schedule and the story stayed fresh. I couldn't keep up with that though so once a week is where I've settled.