there seems to be a lot said about the royal wedding as a factor. surely there was more spent as a result of it, with many people bbq-ing etc, getting booze and food in, not to mention t-towels they don't need

I think the issue was that, with that added Bank Holiday (and the fact that several people managed to extend their 'holiday' by taking that and the following weekend for only 3 days days out) meant that production was down.