I doubt very much that you will ever see a Ryanair aircraft parked on the Western apron in the normal course of events - or Easyjet and Baby for that matter - as all aircraft are parked according to a plan worked out in advance in collaboration with all the airlines concerned. The airside road to DHL should have been built at the same time as the apron, but I did hear at the time that there was some argument over who should pay for it, DHL said as they would derive no benefit from it, why should they contribute to the cost.
The whole thing is just a much cheaper way of making more concrete available for the odd occasions when it is needed such as for diversions, and to tide the airport over until they can afford to extend the 40s apron southwards.
R5.