All the examination pits, locomotive sheds and maintenance bays have already been constructed at GTL. Due to shortage of sleepers the laying of the tracks around the shed has been delayed. They are projecting the it will complete by 2020, but I guess it will start some skeletal operations before that.
WAP5 was originally meant to be at GZB only. WAP5 was imported to run the Howrah Rajdhani and the Bhopal/Lucknow Shatabdis as a replacement for the WAP3 loco. LGD was consulted much later.