And this is now the reply I obtained today from the BBC, after having written to them (!):
Dear Mr Borel
Thank you for your message to BBC Studios Channels.
We are sorry to send a disappointing reply but, as you mention, Swisscom have confirmed that they will no longer offer BBC Entertainment to their subscribers. While we cannot discuss contractual matters, we can confirm that this was Swisscom's decision and any feedback should be directed to the operator.
In the meantime, BBC Entertainment should still be available from a range of operators in Switzerland, including TVT Services, Green.ch AG, KABELFERNSEHEN BODELI AG and Leucom AG.
This list is not comprehensive, and you may also like to enquire directly with local providers.
Thank you again for getting in touch.
Best wishes,
BBC Studios Channels