SFO Issue

NEWS ON SFO: 
PROBLEM DESCRIPTION:

SFO airplanes are being pushed to over Sunnyvale (observed on Flightradar24).


SFO Flying at 2900ft over Sunnyvale
Notice that the big planes are circling over Sunnyvale? It's said to be a "holding tanking for SFO", because the airport needs more time to arrange them for landing.