Hendrik
caveat 1: you must enable Preserve Client VLAN under vap profile to prevent exactly this issue on subsequent reconnect.
caveat 2: Preserve Client VLAN doesnt work across controllers, hence if you have any chance to roam between master/local or local/local, then even balance is not suitable for you.
the broadcast filtering in the controller is now at a point where pools of smaller (/24, /23) are not really required, a lot of larger campuses are up at the /18 size subnets, some even push it to /16
regards
-jeff