CalDav restore or rollback?

Last week I installed a new Todo app and on connecting to NC CalDav, mistakenly chose to have the local (blank) write to the NC CalDav instead of syncing from NC to the local new app. Is there any way to restore this if I don’t have a NC server backup? (I have backups of my NC user files of the Desktop app.)

If it’s stored in MySQL and there’s info on how to access and replace/restore from that, an information on how to do that would also be appreciated.