I am pretty sure that if you had to switch to Unity to see it they would have said so. There’s no sensible way to have content like this on Unity and not Flash, so requiring Unity for Bard means requiring Unity for the game. So they would need to have said:
YOU HAVE 120 HOURS TO SWITCH TO UNITY BEFORE FLASH IS SWITCHED OFF !!!
Except bigger and in flashing letters.
What I think has happened is Unity is taking longer than expected. A lot longer and looks far from ready for final release. And they don’t want to delay Bard anymore as they have content to release for it, events to run, magic boxes and packs to sell.