@A possible use of the spare capacity

According to the comms course I took last year Freeview and analogue use the same frequency band. Digital can be transmitted alongside analogue as it can cope with a lower Signal to Noise Ratio. This is partly why freeview reception is currently rubbish in many areas. When they switch over, they up the digital power and thus you get a much better/reliable signal. So there is no more 'capacity' freed up... though the digital system enables more data to be transferred over the band.