Every time I've flown on the BA flight out of YVR, the CX lounge has not opened before its scheduled opening time, unfortunately, leaving little to no time for it before the boarding of BA84. Being a cautious early boarder, I've never seen the inside of the CX lounge as my flights out of YVR have annoyingly all been on time. 🙄

If you want to eat before your (on-time) flight and have Priority Pass, I would recommend either the Plaza Premium or the Skyteam lounge, both of which have far more substantial offerings than the BA one. It's not fantastic food by any means, but it's pretty okay for lounge catering.