S15 in 123/22307/08. 123/22307/08 used run with 28 coaches. I traveled way back in 2005 from HWH to JU. That time it used to run via AF-SWM route & had upto S15 in sleeper . At MTD, 12 coaches went for BKN after Reversal.
Coaches from S10 to S15 along with 2 3AC Coach & 1 2 AC coach & 3 General coaches went to BKN from MTD.