User blog comment:FairyRaven/Fairy Tail Chapter 365: Fairy in the Jail!, Review and Commentary/@comment-7418318-20131229075039

So Angel is using angel magic... doesn't that give a big hint about the filler being canon?

Think about it: Without the filler (or something else maybe) happening, she'd have spent the entire time since the Nirvana incident in a prison that supresses the magic of the inhabitants. Thus she would have been unable to learn and practice a new magic.

I suppose it's possible that she already had it back then, but why use only Celestial Spirits then, especially if that new magic turns out stronger than her old magic?