My pet name reverted

I just noticed that my pets name has reverted to hearty phoenix, has anyone else experienced this?

this is natural as ure pet lvls up depending on the way it undergoes levelling it will become elder,dire or hearty

http://gw.gamewikis.org/wiki/Pets

Yes they do change name like that sometimes.

Did you give it a /namepet custom name? Is that what you mean it has reverted from?

Yes, the pet was named by me a very long time ago. It must have been a bug that caused it to revert to its default name, perhaps something in Wintersday?