looks like Release 2025.07.01-0813-rolling · vyos/vyos-nightly-build · GitHub fixes above error with minor notes
Just after image upgrade by add system image and reboot, migration failed with unspecified error (didn’t checked thoroughly the issue)
But simple configure | load | commit | save ended without errors and everything looked fine.
AFAIU, PKI structure regenerated from the scratch during migration.
But I needed one more reboot to reload IKE VPN data/configuration for normal work.
At the moment everything looks helsy.