Offline "missions" in AH2 aren't an option for me. The "AI" doesn't even fly by the same physics you do. Meaning a Fw190 can out turn a spitfire and loop perpetually at 300mph without ever losing speed. They fly on preset tracks, or paths, but don't ever have to worry about actual limitations.
In short, the AI cheats, and very badly.
So I don't recommend it to get your "fix" by flying offline.