We could decide to keep the existing documents unchanged and continue to display/edit them with Begin of the insertionCKEditor, at least for a while.
Migrating laterEnd of the insertion Begin of the deletion CKEditor.

ThisEnd of the deletion would allow us to migrate them to file based documents (possibly allowing a selection for the user) but does not seem to offer much otherwise. Begin of the insertion

 In any case we want to understand what our best option for migrating is.End of the insertion