>Leaves little time for Android devices to get the new key no?
It's not so simple, also rotating the keys could affect how devices get app updates, depending on whether or not an app has a V3 signature or not. V3 signature scheme supports key rotation, older schemes do not. OEMs are not required to sign system apps with V3 signatures. The minimum signature scheme version for apps targeting API level 30+ on the system partition is V2.
Affected OEMs can still rotate the cert used to sign their system apps that have V2 signatures and then push an OTA update to deliver the updated apps. Then they can push app updates with that new cert, but devices that haven't received OTAs won't receive those app updates.
It's not so simple, also rotating the keys could affect how devices get app updates, depending on whether or not an app has a V3 signature or not. V3 signature scheme supports key rotation, older schemes do not. OEMs are not required to sign system apps with V3 signatures. The minimum signature scheme version for apps targeting API level 30+ on the system partition is V2.
Affected OEMs can still rotate the cert used to sign their system apps that have V2 signatures and then push an OTA update to deliver the updated apps. Then they can push app updates with that new cert, but devices that haven't received OTAs won't receive those app updates.