Bookworm - your input above suggests that the regulatory requirement for the EIR will be to always file a Z or Y flight plan.
IOW, the departure and arrival will always be formally and overtly VFR.
Is this right?
Otherwise, I can't see how it will fit in with ATC procedures. Coming off a Eurocontrol flight plan, ATC expects you to drop off the enroute section (as directed), and fly the approach (as directed). And a departure will be on a SID (as directed), etc...