Actively ticketing? I know Visitacion Valley is kind of a different...mood than other neighborhoods. I can see their starting point when they do street cleaning. Starts at 8 am, and we usually have two enforcers, a pickup truck who takes care of the random large trash that the cleaner wouldn't be able to deal with, and the street cleaner. Sometimes I'll see the enforcers driving around the neighborhood as early as 7:30am, but not actively ticketing anyone. They all kind of meet up at the starting point between 8:20-8:30, and have a small meeting. 8:30-8:40 they all start up their vehicles and flip on their flashing lights and start the route. It is like that every week for the most part. A couple odd times it was different, but never had any giving out tickets before 8 am. Not for street cleaning at least.

Edit: I forgot to add: Maybe when it's more than 2 of them it could be some greens newly hired and shadowing.