Valve released a small patch which fixes the observer mode bug. The update dealt with the patrol, which helped to identify dishonest players, boosters, account buyers etc. After Valve released the spectator mode update, Patrol members could not watch certain segments of games.
Users had previously reported numerous bugs related to the spectator mode update released by Valve on September 17.
This update is timed to coincide with the imminent start of The International 10, which will be held in Bucharest from 7 to 17 October.