I'm sorry it is not clear to me but when did you see the error message? Was it during the release upgrade process, after you ran "do-release-upgrade" or was it when you did some apt operations after the upgrade completed successfully?
I'm sorry it is not clear to me but when did you see the error message? Was it during the release upgrade process, after you ran "do-release- upgrade" or was it when you did some apt operations after the upgrade completed successfully?