Since, 18637/38 HTE-BNC EXP cannot be extended upto BKSC/DHN. IR should provide a slip portion from DHN to be attached with 18637 at HTE.
The revised CC of combined rake will be:
LOCO-SLR-GS-GS-GS-GS-GS-GS-S1-S2-S3-S4-S5-S6-A1-B1 -B2-B3-B4 (HTE-BNC)-B5-S7-S8-GS-SLR (DHN-BNC).