City of Tucson issued the following announcement on Sept. 23.
Sentinel Peak Park ("A" Mountain) is closed to all traffic, through Sept. 27, as crews repair the rock structure of the "A" on the mountain. Once the mountain reopens on Tuesday, Sept. 28, the City of Tucson will be piloting new operating hours. The park will remain open from sunrise to sunset. There will be no vehicle access on Mondays. Vehicles can access the mountain from 2 p.m.-sunset, Tuesdays through Thursdays, and from 11 a.m.-sunset, Fridays through Sundays.
Original source can be found here.