The present 13023/24 Gaya Hwh express is mainly to serve Nawada and the loop line stations.
Even though with enough connectivity with Kolkata, getting a ticket for Kolkata from Gaya is not easy, a triweekly overnight SF can be run from Gaya to Sealdah with 8 SL, 3 3A and 1 2A and 4 General coaches boosting connectivity and even provide alternative to Dhn, Gmo, Pnme and Kqr