This is the same as the listing I put up yesterday and then expired after a few hours as they sold out. It was available again when I checked at 11:30 so be quick!
This an excellent champagne and is apparently the most popular champagne in France. Much better than the junk you can normally get for this sort of price. The link will take you directly to it and you need to use this voucher to get this price.
Or you could try the 1000 points voucher if you can find anything to spend the points on (I never can).
A few weeks ago it was on offer at about £9.50 in store at the same time but I haven't confirmed that.