[tor-relays] prop224 warning

[Logforme]

Saw a new thing in my tor log today:
Aug 01 11:07:27.000 [warn] Established prop224 intro point on circuit 
799774346

According to google, prop224 is a new hidden service protocol?
https://trac.torproject.org/projects/tor/ticket/12424

Which sounds like a great thing. But why do I get a warning about it?

My relay:
https://atlas.torproject.org/#details/855BC2DABE24C861CD887DB9B2E950424B49FC34