I wish I had a clip to share but...
I was re-watching the latest episode when right after the very first song and Twilight was talking to Rarity and Rarity was working on the cloud patterns when she said.
"Doesn't my sky look fabulous or what?"
Then as everyone was getting mad at her she came up with the line.
"Too last season?"
I had not heard that line before and I had one of those moments where ya go WWHHHAAT!!! (moan groan, Oh my sweet Celestia!, this is why I love Rarity)
Too last season. As in a reference to when Discord in season 2 "last season" turned things into a checker board pattern much like the sky Rarity just created, leading into the chaos that was about to begin this story into Twilight's ascension.
DID ANYONE ELSE CATCH THIS! cause I'd hate to think I'm going nuts by myself.