I have acquired a few letsencrypt certificates over the past several months but so far no expiry notification emails have arrived. The certificates are renewing fine but it would be nice to know.
I am getting other mail from letsencrypt but assume the notifications are sent from a different source.
I am guessing that the sending mail server’s IP is blocked either by my firewall or by my mail server. Can I find out what IP (range) the notifications are being sent from, please? I can then try to unblock whatever is holding them back.