Well, I found this in the Appendix 1 to JAR-FCL 1.055:
"7. If an FTO wishes to make changes to an approved course or to its operations or training manual the approval of the Authority shall be obtained before the changes are implemented. FTOs need not advise the Authority of minor changes in day-to-day operations. Where any doubt exists as to whether a proposed change is minor, the Authority shall be consulted.
8. An FTO may make training arrangements with other training organisations or make use of alternative
base aerodromes as part of its overall training organisation, subject to the approval of the Authority."
It says nothing about registrations though...