Since the inauguration of the new Hauptbahnhof/ZOB terminus and a few new elevated platforms being built on the line 10, the operation of TW6000 tram sets became impossible, so TW2000/TW2500 sets are used for daily operation. Line 12, which only operates during the night service on weekends, can also be operated with TW6000 tram sets, although the first and last passenger doors have to remain locked, which is due to some of the new platforms being too short.
During my night shift I got the very rare opportunity to drive one trip on line 12 with a TW6000 set.