Don't worry you are not missing out. Sephora is no longer in the UK but they used to be @Pineapple . Debenhams round our way could not confirm any dates to me, will check again at the end of the week in case things change.
I'll nip in there during the week just in case, but I will definitely go at the weekend @Pineapple . So either way I should know about my local Debenhams in Uxbridge. Otherwise it'll have to be Westfield