I wanted to post some wide text but I don't have the code snippet button enabled on my toolbar. But hey ho!
Definitely going in the right direction and beginning to understand the nature of the problem a little better.
What I meant was, nobody edited the Postfix configuration manually. I tried both MailPoet and MailerLite so maybe they might of done it programmatically, but I don't think so.
There's no SMTP plugin on the site. All I did to use SES was `sudo webinoly -smtp` and enter the SES SMTP credentials.
Deliverability Report
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https://mxtoolbox.com/deliverability/f637f5b9-9efb-4bd8-b3ce-a3c2da39bc88
sudo log -mail
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https://i.imgur.com/41ZQHg1.png
Personal Gmail address
----------------------
terence.milbourn@ primary
SES verified G Suite sending addresses
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terence@ primary
admin@ alias
hello@ alias
sales@ alias
support@ alias
wordpress@ alias
Route == Result
---------------
sales@ to terence@ == sales@ terence@ [OK?]
admin@ to terence@ == sales@ terence@ [Error]
terence@ to terence.milbourn@ == sales@ terence.milbourn@ [Error]
terence@ to sales@ == sales@ sales@ [Error]
terence@ to hello@ == sales@ hello@ [Error]
terence@ to support@ == sales@ support@ [Error]
sales@ to admin@ == sales@ sales@ [Error]
sales@ to support@ == sales@ sales@ [Error]
wordpress@ to support@ == sales@ support@ [Error]
I think you can see the picture -- when I send from any alias address, something (Postfix?) changes the sender to sales@, and when I send from any alias to any other alias, it changes both addresses to sales@.
This holds true when sending from alias to alias, and primary to alias, but not alias to primary. In that case it changes the alias and leaves the primary as intended.
I don't know what happened to any that didn't arrive.
If you want me to disconnect the Webinoly SMTP routing to the SES relay I can do that, but I don't think it will make any difference. Let me know if you want me to and I will.
Terence.