When the CST crew has departed the facility with the last group of inmates being transported and all those being released at court are gone, lockup personnel shall inventory all keys, radios, chains, and equipment in the lockup, note any discrepancies, and secure the control area. All interior cell doors shall be left unlocked. Exterior doors shall be locked. The Master Keys for the lockup shall be secured in the Branch Office, in a location designated by the Branch Supervisor.