I can answer your questions because I'm the one that filed the issue previously referenced by nusenu.
What are the exact torrc lines?
One relay where I see these log messages has a public address of 51.15.48.254 while the relevant torrc lines are as follows:
ORPort 10.8.169.135:443 ORPort [2001:bc8:4700:2300::25:c07]:443 DirPort 10.8.169.135:80 OutboundBindAddress 10.8.169.135
I don't think this warning should be triggered in the setup you describe, but I'll need to re-read the code to check.
I'm not sure of the exact network setup because it's not something I have much visibility into, but the affected relays have a single private IPv4 address and a single public IPv4 address and seem to behave like a 1:1 NAT as far as I can tell.