I am facing a similar issue with occassional 504s that appear to happen for no reason. @daniel.tomcej have you got any suggestions (or are there any good guides for this) for how I'd start debuging this ?!
I thought this might have been a stale DNS record issue, but since traefik goes straight to the pods, then I don't think this could be it. As an alternative, is there any way to configure traefik to retry that request ?!