Normally it is a Tuesday collection, alternating green then black bins. Christmas Eve, they moved it a day early on the Monday, for the black. Tomorrow New Years Day, would be the green bin, so I checked on line and as you would expect with days being lost, it will be a day late- Wednesday.
A few seem to have assumed it will be collected today and put theirs out, then everyone else has assumed they were correct and almost without exception put their bins out too - all except me, because I bothered to check :-)
You can see how there might be mass sightings of a clone at Gatwick :-)