I am replying to this thread to add my own comments.
I too wanted to watch the Man City v Liverpool game - highly advertised by BT Sport - probably the most eagerly awaited match of the season so far. I was round at my Son's house for dinner and to test things out I tried to see if I could watch the match before - West Ham v Arsenal. I was watching on my Samsung Galaxy Note 10.1 via son's wifi and had absolutely no problem watching it.
Could I watch the Man City v Liverpool game? Could I F**K !! aLL i kept getting were vc013, vc012 OR vc014 ERROR messages.
I haven't the time or inclination to search the forum to see if other users were similarly afflicted, I guess they were, - almost certainly due to demand.
Not good at all BT and probably a game stopper for me. I will be seeking termination of contracts through the relevant channels - if you cannot deliver then you loose customers - full stop!