Thanks for that Ivan - I was also of the opinion that Aaron only explicitly answered half of the question, and was unsure what it meant for when you can reveal AF.
Curiously, this now means that you can roll damage, not like the result and reveal Akiro's Favour for a reroll, but you can't roll a burn, not like the result and reveal Adramelech's Touch for a reroll modified effect. I understand why (and to my mind defining 'event' rather than removing it was the way forward), but it's a curious anomaly, and I'm sure a number of more casual players will hear one rule, and apply it to both scenarios erroneously.
Having removed the event option in upkeep, and made the no retroactive effects from revealing rule, I'm glad it was finally ruled this way though. AT was a weak niche card made very weak, AF is an average card that would have become weaker, and I'm all for making as many cards useful as possible. It seems the better ruling in a broader sense too.