I was at A27, and I don't think anyone was helping anyone (sidewise). The Bishops were leveling the ack so they could vultch (no real attempt to hit hangars), and I saw no Knights present. I was vultched ceaselessly, 'til my wife made me go out and work.

Personally, I don't know what four sides would have done to prevent this... all I can give you is the same advice always given- if you don't want vultched, don't leave a CAP'd base. (I did it for the hell of it, because if they were seriously trying to capture the field without closing the hangars, it wasn't going to happen while I was on.

)