Not additional platforms but pitlines will lead to new long distance trains bro.
The reason they could be building extra platforms is, NZB is too much congested as of now and they may start shorter train services from NZB.
Example of congestion at NZB is sometimes there are 3 trains at the same platform in early morning. NZB-KRMR, NZB-KCG, NZB-NED all going in different directions are on PF3.