21st MDG early release Published March 2, 2009 PETERSON AIR FORCE BASE, Colo. -- The 21st Medical Group, including the main Pharmacy will close on Mar. 17 at 2:30 p.m. for Commander's Call. The BX Pharmacy will close at 2:45 on Mar. 17. The 21st Medical Group will reopen for business as usual on Mar. 18.