Oh don't you worry there is no way I'm paying full price on principle. I've already emailed them twice and told them I will be doing my Christmas shopping elsewhere if the offer isn't going to be made good. Lol, I'm not a member of Facebook but I just had a look at the M&S page there and it's full of complaints !
I guess their customer service team are being kept busy today. Just got this reply from an email I sent last night !
We're really sorry that you had problems visiting our website. Lots of customers visited M&S.com last night which has caused some performance issues for additional people attempting to access the website. We've looked into this and I'm glad to say that things are now back to normal.
We're really sorry that last night's problem affected you using your discount. We can certainly honour that for you today. Please try replacing your order and contacts us after and we apply the discount.
Kind Regards
Matt Chamberlain
M&S Customer Services