flew SFO-LHR saturday on954 (772). Am returning Thursday on the 744.
When I booked I was waitlisted for upgrade to C, which did not clear until early August. My inbound on the 744 cleared at booking.
The flight Saturday was completely full in all three cabins. One of the FAs told me that every seat was taken. He is London based and told me that lately all the west coast (LAX/SFO - LHR) flights have been full.
Both of Thursday's flights to SFO are showing seats available in C and F.