I re-signed the ipa using fastlane, without changing the signature, just turning off some plist features，only change UIFileSharingEnabled to false
After publishing to testflight, that idfv has changed compared with the package that is not re-signed ipa.
At present, it seems that not all users' idfv has changed, only some of them have changed, which makes me very confused. I don't know what happened in it