APN Auth key

Currently our app is using the APN auth key that was created from developer portal. No one has access to the key, We are moving to new firebase project and don't have access to APN auth key(one time download) according to doc https:/firebase.google.com/docs/cloud-messaging/ios/certs. If I create New APN key will it revoke the old one ? Say if I use New APN key to test in development app it won't interrupt any notifications in production app with old key ?

Second question answer will be it won't if I just update in development app. Just wanted to make sure. Any help will be appreciated.

Creating a second key will not have side effects on the first key. Once you have finished your transition, you can revoke the first key.

Although, if that first key is being used in production currently, someone must have access to it, as they would be using it to generate authentication token.
APN Auth key
 
 
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