Download IPA from Crashlytics

I'm using Crashlytics to distribute an app for Beta testing.

While it is easy and convenient to install the app on devices from the Crashlytics app, I have not been able to figure out how I could download only the IPA from the Crashlytics server.

Background: I need to get the IPA for automated testing. My test environment will re-sign the IPA to be able to install it to test devices, so going the Crashlytics app way doesn't work.

What I need would be a download link for the IPA as it used to be available in TestFlight or Hockeyapp.