Just to add a more recent data point: I made a couple of cheap EU-CH r/t bookings yesterday night on the Swiss.com website and had second thoughts, but only the Swiss US website explicitly mentions that cancellations within 24 hours qualify for a full refund. I called the local service center this morning (within 24 hours of the original booking), and they were able to cancel the bookings for a full refund. The money will go back to my original form of payment (credit card). Hope this can be of help to someone!