I created an alias using SimpleLogin domain, used it for a while then deleted it.
This was more than 30 days.

Several months later I gave out that address to a shop because I did not remember I had ever used and deleted it.

The shop said they sent emails to me which of course I never received because that address is permanently deleted.

SimpleLogin blocks emails to an alias address we have deleted:
that means they must have a list of addresses we have deleted.

Why can we not see that list so we will not hand out those addresses in future?

(yes, in future I will disable instead of delete but that is no help in the meantime)