VMAs and CMAs had them. Billboard had backstage cams which is where this gif came from. I think that’s it.
Here’s a compilation I think that’s all I know of:
Billboard Awards 2013
Last social media interaction was this tweet https://twitter.com/katyperry/status/337414131609108481 and Taylor’s reply: https://twitter.com/taylorswift13/status/337418606264610816
No idea what happened since, maybe it had something to do with her going back with John, maybe it has to do with how she took Taylor’s dancers in the middle of her tour (they were originally Katy’s, but they left mid-tour to go back with Katy. Taylor unfollowed them all on twitter and they were all hangin with Katy.) And after that drama there was this: If you notice at last year’s VMAs, in an interview she ignores Sway when he mentions Katy - http://www.mtv.com/ontv/vma/videos/taylor-swift-tells-sway-shes-super-excited-about-lady-gagas-performance/943309/#id=1712592
Just throwing out some ideas, I don’t know if we’ll ever really know the reason(s) behind their fallout.