ARUP, it's A2S meaning air to surface. This is the command given to your wingmen to rejoin formation when attacking ground targets. The rejoin formation works only when "ground pounding". For A2A combat wingmen will rejoin automatically once no enemy planes are in sight.
"Take the cylinder out of my kidneys,
The connecting rod out of my brain, my brain,
From out of my arse take the camshaft,
And assemble the engine again."