Nope, we only know what was in the dev stream that most recently mentioned it (I can’t remember which stream it was, sorry).
There’s something niggling in the back of my mind that this was brought up on that same dev stream, but I can’t remember for certain.
There was also a discussion about the ability to delete here: Could the "World Hub" be used to delete non-existent airports?
TLDR: Nothing official but when we put the pieces together from the dev stream and what we already know, the general consensus was that we don’t think so because deleting an airport isn’t a SDK option. It’s probably worth giving it a quick read though as it contains everything we know about whether there will be an option to delete.
But then again, we could all be wrong because we don’t actually know for definite yet 