Right now they have 4 747s.
2 used for YVR - HKG
1 used for YVR - NRT
1 used for YVR - TPE
They don't use 747 for HNL anymore. They have switched to 767s.
Even if 1 747 is out of service, I still don't think all the 747 routes should be affected. Maybe it was a conincidence? But it is very rare though as all of them delayed for almost 4 - 6 hrs today.