Question Author
Thanks very much.
That is pretty clear:
"British nationals travelling to Sharm El Sheikh, Dahab, Nuweiba and Taba resorts only, for up to 14 days, do not require a visa, they shall receive a free entry permission stamp upon arrival. If you intend to travel out of the mentioned areas or overstay, you must obtain a visa."
"Visas can be obtained........on arrival by payment in Sterling or USD, for stays of up to a month."
As it seems they don't accept euros for British passport holders, I have sent an e-mail to the Egyptian Consulate to ask how much it will cost.