Mass changing "sendas" passwords?

[Achim Heger]

I have quite a special mail setup: I create a new alias on  my domain for every single subscription.

To be able to send with this aliases, I send via smtp.gmail.com, to avoid showing the "original sending user"

of my domain.

This leaves me with a big list of mail addresses which are configured as "sendas", every time I change my password

I need to change it for every "sendas" instance. My hope would be I can change that with GAM.

I'm not quite sure if that is implementet at all, I haven't found it in the documentation yet.

I'm only able to list the existing "aliases".

Any input? Maybe ideas how to create a better solution for my wish to track where a certain mailaddress of mine was "leaked"?

Thank you for an ideas.

Achim