Reverse DNS IPv6 issue?

Not sure if this is related to #40288 (closed), but since version 0.4.5.6 I experienced an issue with my Tor relay node not being published.

Received following log warning:

Feb 16 03:15:56.000 [warn] The IPv6 ORPort address xxx::bff does not match the descriptor address xxx::bef. If you have a static public IPv4 address, use 'Address <IPv6>' and 'OutboundBindAddress <IPv6>'. If you are behind a NAT, use two ORPort lines: 'ORPort <PublicPort> NoListen' and 'ORPort <InternalPort> NoAdvertise'.

However, my ORPort published in torrc config is:

ORPort [x::bff]:43261

It is being caused by my reverse DNS on IPv4, which resolves to my domain. If AAAA for my domain is looked up on it returns the ":bef" address. I fixed this by changing AAAA record for my domain AAAA record to ":bff". Somehow the "auto-detect" feature is looking up reverse DNS and checking the corresponding AAAA record for the domain I guess.

Is this a bug or should I make configuration changes? I would like to be able to revert my AAAA record to ":bef" without it breaking tor node on ":bff".