Shipping empty bike case within Europe?

[TT Tandem]

Saw the post about Bike Flight and thought of a question. Planning a European tour, not a loop, and wondering about having our bike cases shipped from Start Point to Destination. Anyone here ever done this? They are S&S cases.
Thanks

[foo_fighter]

Not sure about shipping costs for the hard cases but the backpack cases pack down pretty small. Though you probably already have the hard cases.