I am not sure about construction progress, but this was meant to be done in November 2013, apparently. I understand the bridge should have both steps and ramps. I hope it does not seem to dwarf the site too much...!
It is a sensible step to build a bridge, as a train stopped at either of the platforms can easily hinder the views of the adjacent line. Given many other services could, in the mean time, run non-stop through the station, they may not be seen until it is far too late, especially if the crossing user(s) in question was/were young or elderly (remember that the station is not far from various houses and therefore within walking distance for a number of local residents - indeed, with any future implementation of much-requested higher service frequencies, it could be rather better-used). In addition, the provision of a crossing is crucial to the station's functionality, and it is therefore very much a required feature which will only get busier.