They already have a shared stand sequence. But no, they will never be merged as there is no physical link between the two. It also wouldn't be just a case of demolishing the spiral car park either. The John Lewis and Fenwick freight docks are accessed via the entrance to Eldon Square bus station, as are the collect by car stations for those two along with M&S. And there are major plans to transform the public highway along Percy Street which should make a massive difference to traffic levels.