got a puncture today on the rear offside wheel, took it to the tyre shop and when they removed the tyre it was nearly below 1.6 ml, it's been on the car since new so it's covered 42,000 miles, but upon removal of the tyre we found out there was an excessive amount of wear on the inside of the tyre, I'm thinking it's a wheel bearing, put the rear right window down and drove for a bit and I must say there is a bit of a whine, taking it in next week for it to be inspected. Would it be covered by warrenty, 2013/62 plate 42,000 mile?

I can't see why it wouldn't be - 42k miles and a 2013 model.  I had a wheel bearing covered on an Octavia a few years ago. 

More likely rears are saw toothed which can drone.

What pressure do you run, and what brand of tyre? Some are more prone than others.