I want to set up heroku and my MX records such that whenever I spin up a review app, eMail can already be routed to it.
For example, if I create a new review app and heroku assigns it the name:
company-feature-email-123abc.staging.company.com
I want there to already be be a wildcard MX record in my zone file to successfully route eMail to that review app.
What's the right way to phrase this MX record?