If you're joining at Wotan from Filton or Briss, standard join level is actually 100 to be 90 or above by Wotan. If you want a level below the airway then tell Filton, they will get you airborne below L9 up to 70 (during the times that their radar is operational) then co-ordinate onwards with Lyneham. At weekends, we deal with it as Filton seldom have radar then.
Our inbounds from the east don't need to be at 80 at Pomax, that's just the level we can descend them to before Pomax due to the airspace base.