[gardenweed]

Originally Posted by jhollington

Yes, by default that would be the case, but there's an easy way around it....

When you setup the "Identity" for each of the "Basic" users, simply make sure you also select the option to Send messages using an external SMTP server, and specify smtp.fastmail.com, along with the username and password for your PRIMARY "Standard" account (keep in mind that you'll need to generate an App Password for this if you're using two-factor authentication on that primary account).

Good trick.
Thanks for that.