They also tweeted that the reason is "There are not enough hotels participating this week for the offer to go live! "


Based on which I'd assume when they launch the offer next Monday, there may not be any availability for the Easter weekend.

As far as I remember, when I looked last week the only London availability for this weekend was the Pullman St Pancras and Novotel & Ibis Styles Excel, so a lot less than normal.