A bit late to answer as you've probably already found the info but anyway:
The air suspension is speed sensitive i.e. if you go over a certain speed it will automatically lower to keep the C of G down then when you go slower it pumps back up in rediness for rough terrain therefore if you're going round town it will be up and down all the time but if you're on a long run it will stay constant. You can override it to the low setting but not to the high setting for safety reasons. It also has a super low setting for carparks or people getting out.