Yes to the first, and pretty sure about the second. And the two accounts were intertwined in many other ways: one was the recovery address for the other, one forwarded its email to the other, they were both accessed at the same time from the same IP over the years.

The only trigger I could see was that I had not logged into the account I lost for a while (months).

Baffling, but it clarified that relying on a single company for multiple services was quite foolish, and I've since spread my accounts around to multiple vendors. Highly recommended.