[S7E10 Spoiler]Are Daybreaker and Nighmare Sun/Solar Flare the same being?

I realize that technically Daybreaker isn’t “real”, being born of Starlight Glimmer’s (and/or Celestia’s) fears, but both her and Nightmare Sun from the CCG are the same concept: A version of Celestia that succumbed to the same forces (be they internal or external) that corrupted Luna into Nightmare Moon. Now that Daybreaker has appeared in the show, does she supersede Nightmare Sun?

For all intents and purposes they are the same character. There’s nothing preventing Nightmare Star from also being used, but until said time comes then if Celestia ever goes evil then she’ll most likely do so as Daybreaker.