I recently updated my MX records to reflect changes to my mail host. If you are making MX changes and are using MTA-STS, don’t forget to update your MTA-STS text record with valid MX servers and the MTA-STS serial number in your DNS TXT entry.
My previous MTA-STS ID was
id=20160831085700Z and taken directly from the IETF’s draft MTA-STS page. If you remember correctly, any changes to your MTA-STS record require a change of the ID. I’m not sure if the value has to be greater than the previous ID field or if it can be any change of letters/numbers so I assumed it required a greater value than before.
My new MTA-STS is
id=20190217090400Z and, for my sake, generated on the date/time I made the change and broken down as follows:
id=20190217090400Z – Year
id=20190217090400Z – Month
id=20190217090400Z – Day
id=20190217090400Z – Hour
id=20190217090400Z – Minute
id=20190217090400Z – Second
id=20190217090400Z – Z = “Zulu” = UTC time