Read it last night and I agree with you. That's been my hunch for a while. The General is getting close to figuring out what is going on. It'll be a while before anybody figures out why it is going on, though, IMO.
I didn't see anything that leads me to believe it will end at 40, though. Did Seeley state that it would be? I can't seem to find it.
It's nothing that Tim Seeley said.
IMO the plot has picked up so much in the last few issues, it makes me think, fear & guess that the series will end some what soon --- my guess, issue 40.