I am not sure how it happened ( I just know it wasn't me !! ) but the episodes are now completely messed up in Charlie Brookers Screen Wipe. They are in such a state ( you will see when you look ) that changing them via edits was a bit beyond me.
I got the info when I first added the eps a while back from ...
... having two seasons 1 of 3 eps, and one of 4. Not sure what is going on now
Hope this can be sorted out.