Yesterday there was a minor derailment at SBC station in the afternoon, they might have taken some time for repairs and consequently chain effect on all trains, i guess that must be the reason for delay.
I travelled yesterday by MAS-SBC DD and it halted for full 90mins at KJM, then took 1hr from KJM to SBC and reached SBC late by 2hrs.
They even announced at KJM station that the train would be halted for 90mins.