SystemInfo.DeviceUniqueIdentifier value change when updating app through Test Flight

Hello,

I've been using SystemInfo.DeviceUniqueIdentifier to identify users in my game.
The live version (on the app store) was built using Unity 5.2.4.
I'm now planning to push an update using Unity 5.5.3.

But when I'm updating the live version with the new version through Test Flight (or Xcode), the SystemInfoDeviceUniqueIdentifier value will change and break many things in the game.

I did not find any information regarding any changes on that method in the recent unity versions.
Is...

SystemInfo.DeviceUniqueIdentifier value change when updating app through Test Flight