Make relays try IPv6 ORPorts for directory uploads and downloads
Using IPv6 ORPorts will make relay behaviour consistent with future client behaviour.
The only difference is that relays will also use IPv4 DirPorts, but clients will not.
Relays should try to upload descriptors using IPv4 and IPv6 as well, to detect authority connectivity issues.
To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information