Personally, I discourage people to run to stationary AAs. on Muttrah when I'm doing CAS as I know where they are and I like to be the one that takes them down so I could start a respawn timer. What I usually do is warn people on chat twice and then do a hydra/hellfire run on the AA. I know that this may seem a bad habit and be pain in the arse, but it is really annoying when you have someone next to AA and knifing the gunner. Specially when knowing that bots don't have weapon cooldown timer and they can fire instantly as they spawn on the weapon. Like Semler said, communication is very important in these kind of situations, but I personally think, that inf should stay away from stationary AAs unless asked otherwise from CAS squad.