Trouble with save data on updating after App Transfer

I am currently having a problem with most recent update of my iOS application SUPERSTAR PLEDIS. I recently did an App Transfer to successfully move the rights to this application from my old company to my new company. However, upon releasing an update to the app, iOS users were unable to load the save data stored on the device.
While I have yet to pinpoint the cause, I suspect the problem lies in storage of PlayerPrefs (I am working on a Unity application, which stores PlayerPrefs in /Library/Preferences/[bundle identifier].plist). I have double checked my build and my bundle identifier has not been changed (either in Unity or in Xcode).
Is it possible that as a result of the App Transfer or related activity (change of Team ID and App ID prefix as a result, new provisioning profile and so on) my app is in a seperately curated sandbox from the previous version and unable to access the previous save file .plist? If so, is there anyway to "bridge the gap" so to speak and maintain save file consistency in new app versions?
I realize the problem may be Unity related or caused entirely by my error, but any help or advice in resolving this that could be provided would be greatly appreciated.
(I had thought to check and see if two seperate .plist files existed in the library folder to see if my assumption was correct and the old save file was being ignored, but due to iOS' security features I have not found a way to see that information. Is there a method to do so?)

We had similar problem just recently, still trying to find out why PlayerPrefs stored in app library was changed / removed while updating app after transfer between companies.

Did you find the reason? I am about to transfer my app to another company.

Trouble with save data on updating after App Transfer
 
 
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