So, I came across a different way to avoid getting booted from the server for being afk(good for servers that still have a queue.) The other method posted doesn't work for me.
What you do is go into a space mission, fail the mission, and leave your screen with the 'you lose, would you like the retry or quit' option up. I've been going afk at that screen and it for some reason doesn't kick you from the server! Hopefully the queues die down, but until then this trick could be handy.
So to reiterate:
1-Hop into a space mission
2-Lose
3-AFK at the 'you lose, quit/retry' option box screen. (Alternatively, you can just afk upon entering because you'll lose from not doing the objectives!)
Hope this is helpful to someone!
Cheers