I love Airmail and this may be because i'm always using the beta versions and they come out frequently (thank you!), but when a notice pops up that there's a new version out Airmail stops fetching mail. That can happen when you're away (say for a week) then the process is one pop up per new version that came out in the week must be dismissed and only after you've done them all will it fetch mail from that last week. Thats a lot of waiting and pain. I kill the app (force quit) in scenarios like that just to avoid the click-a-thon.

Minor thing but would love a fix.