@Shadowbech in a sense it is - I surmise they are storing some eSIM info (line info in case someone has multiple eSIM lines active) in the Recent call information, and when the transfer to a new phone occurs through the Migration Assistant, all the info is carried across. Now on the new phone, a new eSIM connection has been established with the carrier, so that info is no longer valid.
It's an interesting conundrum though of how it could be avoided; if an eSIM connection had been established on the new phone by the time the migration occurred, the migration could employ the new eSIM connection into in the Recent entry. Yet, that might be invalid too, or certainly unwanted by the user - say someone had two eSIM connections on their old phone, and a Recent call entry was to work - yet on the new phone only a personal line was set up. The user might tap and dial quickly not realizing they were calling Japan on their personal number, not their work number.
In my case the eSIM was already set up on the new phone when I did the migration, as I set the phone up new, with no personal logons, to do the 16.0.1 upgrade, then I reset it and did the setup with my data from the old phone. But if someone just set up and migrated data to the new phone in one action, I seem to recall the eSIM line would not be set up at the point of the migration. So what does it do then - just put blank info in the Recent line entry? That would necessitate an error message too, as a Recent call would be tapped and their would be no eSIM info.
This is all just my unsubstantiated theory of course. But all in all - in the world of eSIMs - just clear your Recents list when you move to a new phone 😀
