Push notification after iOS app transfer

It's not a direct answer, it's an alternative, but
As a person who was worried about push notification before, I would like to share my knowledge.

First of all, if you change your app's account via iTunes connect,
I have a question about what happens to the device token ID.
I can't answer because I've never experienced it before...

However, it is recommended that device token IDs be implemented on the assumption that changes occur.
The reason is

• The device token ID specification was changed when iOS6→iOS7 was updated
  Up until iOS 6, allocation per device was changed from iOS 7 to allocation per device and app.
• The device token ID is now changed every time the app is installed from iOS 9.
  This means that once you uninstall and reinstall, the device token ID changes.
• Two specification changes are scheduled for this year.
  1: Increase the device token ID size (change to 32 bytes→100 bytes)
  2: Development, production certificate becomes one (previously, each certificate had a different ID)

This is because of the background of the past and future plans.

Therefore,

• Keep the issued device token ID inside the terminal
• Verify device token ID for each app launch (if booted from a dead state)
• Update the value if the confirmed device token ID is different from the device token ID stored inside the terminal (and the DB inside the terminal and on the server side)

I think it would be good to say that

If this is the case, we will be able to respond to your concerns.

Of course, it won't be updated unless the user starts the app, but
The device token ID changes specifications with each iOS update, so
Whether or not push notifications will be delivered should be considered as best effort.

I hope it will be helpful even a little.