I doubt it really works that way. There will be a next edition only if the first one is a runaway success. This is really a niche market. It is great (and exceptional!) that Saint managed to get it printed at all.
And the time spent was likely huge compared to the return. I doubt Saint was paid minimum wage for it given all the hours he undoubtably put into it. So even if the publisher wanted to, it could still not happen or not happen for a few years.
But of course, I am only speculating.