sounds as if they are adopting some of the French habits… no more gazumping…
Isnt it the sellers fault for gazumping (discuss) ?
They are the ones who accept the higher offer - alternatively as a seller wouldn’t you want to know if someone is prepared to pay more?
A Seller should not accept an offer… if he is not happy with the amount…
The Seller can always Sell by Auction… 
But Stella, more is more!
Does gazumping happen in France?
Sorry Mat… I thought you knew…in France, once the Promis has been signed… the Seller promises to Sell at the price agreed… and the Buyer promises to Buy at the price agreed and subject to certain agreed-conditions being met.
The Seller cannot back out in favour of a higher price from someone else.
If the agreed-conditions set by the Buyer… are not met… the Buyer can back out.
I should know we have been through the process - I suppose there is a chance between offer verbally being accepted and Promis being signed for someone else to “interfere”.
Exactly… which is why I always advise a Buyer to get the Promis signed before buying new curtains…