Thanks for the fix Frankie 😉
The SendGrid plugin overrides the wp_mail function, and allows you to choose between SMTP and their Web API.
So if you have a call to wp_mail that would otherwise work fine with SMTP, then if you use the Web API, this will work fine for you.
Also just noticed a bug in the time_zone settings (line 148 of enable-media-replace.php). If the timezone is set with an offset (eg. UTC-7) rather than a specific timezone, a notice is given in the “Revised” field of the “Edit Media” page (and probably other pages too).
Didn’t have the time or energy to figure out a proper fix right now, just changed my timezone to a specific city.
PS: The <br>s in the code block above shouldn’t be there, appeared after editing the post…