I've booked a car in GVA.CH for March 2017. I've just received this from BA.
Dear Customer,
I am contacting you with further information regarding your Avis car hire reservation in Switzerland.
A new EU Directive means that any customer wishing to drive into another country must advise Avis at time of pick up. EU residents can only drive a vehicle with an EU license plate out of Switzerland therefore all customers will be asked to sign a document when collecting the car to advise of their plans. Avis endeavour to provide all EU customers wanting to drive out of the country an EU plate car. If you are given a non-EU plate car and you drive out of the country you could be liable for a charge at the border (10% of the value of the car). This charge is made at the border therefore it is imperative you sign the document at the depot so that Avis can give you the correct vehicle for your plans.
As part of our commitment to customer service, we like to ensure that our customers are made aware of such information prior to travel. This email is for clarification purposes and I trust this will not affect your stay or enjoyment in any way.
In closing, I would like to thank you for booking with British Airways Holidays, and wish you an enjoyable trip.