Its not a suprise!
Only the timing of the event.
I suspect your average family from Stoke off for their two weeks in Ibiza Sat AM have NOT been monitoring the media......but I may be wrong, i usually am !
BUT pretty sure this would have been mentioned on national news if it were London !
I'm sure as you imply it will all go super smoothly after all closing the main arterial road from The South and West should make little difference to the main day to day traffic flows.