Investigating, it appears that the interfaces are getting renamed by udev in the initramfs, which pushes their name_assign_type value to 4, and udev refuses to rename an interface if the name_assign_type value is 4.
So, I can make this scenario work if I do:
4. sudo update-initramfs -u
5. reboot
After rebooting, the interface is correct.
I'll add a systemd task here in case we want to poke at allowing renames even if assign-type is 4.
Investigating, it appears that the interfaces are getting renamed by udev in the initramfs, which pushes their name_assign_type value to 4, and udev refuses to rename an interface if the name_assign_type value is 4.
So, I can make this scenario work if I do:
4. sudo update-initramfs -u
5. reboot
After rebooting, the interface is correct.
I'll add a systemd task here in case we want to poke at allowing renames even if assign-type is 4.