I had problems on Saturday too. Never noticed till Demons on ITV wouldn't work. Worked on freeview box and Sky box upstairs. I had to cancel all recordings to get it to work and then I found that anything being recorded was all that I could watch and I could only watch and record the one channel at a time which is pointless.
Sky told a friend they need a new box. I did a full system reset and fixed it myself. My friend had to pay a callout fee and probably pay for a refurbished box which was probably a box taken from his neighbour who had the same problem. The Sky guy did a full system reset at my friends house when installing it and this whole affair smells of a scam!
Full system reset can be done as follows:
You should press services>system setup> then 0 then 1 then SELECT
Now you will have the engineer setup.
Try planner rebuild first (which SHOULDN'T loose anything)
If this doesn't work do a full system reset which will reformat your HDD.
The full reset will loose ALL recordings and things you have in your planner.
I personally just went straight to a system reset and it did work.
Seems like a lot of Sky customers got duped by a similar update scam back in November. An error that Sky refuse to accept as being their doing.