This is an excellent example of why HAWK/PHB signals are really bad. Bicyclists approaching from the cross street see a flashing "don't walk" signal, which typically means mainline traffic has a solid red. But for HAWKs, it's a *flashing* red, meaning that drivers proceed "with caution"
Make it stop! HAWK signals are a hot mess. I use the crossing at Delaware/San Pablo Ave in Albany dozens of times a week. The signal confuses drivers, the solid red cycle only last a few seconds, & without fail at least 1 driver is guaranteed to just blow through the solid or flashing red cycle.