BST 2010 [ edit ] errors File:Stagecoach_South_Downs_15602_GX10_HBL_rear.JPG aborted File:Stagecoach_South_Downs_15602_GX10_HBL.JPG aborted Stagecoach in Portsmouth 18191 (MX54 LPY), a Dennis Trident / Alexander ALX400 in Queen Street, Portsmouth , Hampshire on route 21. Stagecoach in Portsmouth 18191 (MX54 LPY), a Dennis Trident / Alexander ALX400 in Queen Street,