It will probably be the DFT who will have to decide to allow refunds, even into the shape of credit notes/RTVs.
No doubt they will only go down the lines of "you can change it for free" which for some is as much use as a chocolate teapot
Yes, you only have to see how airline passengers have reacted to airlines offering a free change of date or voucher. In some cases passengers have told airlines they don't want the voucher even if it's for 120% of the value of the flight ticket.