Flutter build ipa not working in Firebase app distribution

I am using Firebase App distribution over a year now to deliver my Flutter app releases to my testers and it's working fine by following this process :

• Open XCode and make a release of the app
• upload the .ipa to Firebase app distribution
• If the testers download it the first time, add their device to my apple dev account
• Make a new release with the new provisioning profile
• The testers are able to download the release

Now i am using flutter 3.7 and i am using this command :

flutter build ipa --obfuscate --split-debug-info=/Users/foxtom/Desktop

It's working very fine apparently, i do have a .ipa file generated etc..

However, when i upload this .ipa coming from this command, all my testers (including myself) are getting Device is registered, all set ! from Firebase app distribution.

This is the message you get when the device is registered the first time and that you have to make a new release... So i have made 3 different releases after this one and the message remains the same.

Note : if i do the same release using Xcode, it's working fine.

I can't figure out if the issue is from Firebase or Flutter here... My guesses are :

• Flutter doesn't take in consideration my provisioning profile
• Firebase app distribution has an issue "veryfying" obfuscated builds

I have raised a ticket to Firebase support in the meantime, but i would like to know if someone had already experienced this and if there is a current solution.

EDIT : i have created a flutter issue to get more insight

You have to add the flag --export-method=ad-hoc :

flutter build ipa --obfuscate --release --export-method=ad-hoc --split-debug-info=/Users/foxtom/Desktop