The trains from Mysore proceeding to Chennai will stop at Katpadi from the 9th of May due to maintenance work.
A notification released by the Southern Railway mentions the following:
"The superfast express train (12680) from Coimbatore to Chennai Central will be stopped at Katpadi Railway Station on the 9th, 10th, and 16th of May. On the return trip, the superfast express train (12679) from Chennai Central Station will start from Katpadi instead of Central.
The superfast express train (1261) starting from Mysore on the 9th, 19th, and 16th of May will be stopped at Katpadi.
The Express train from Chennai Central to Bangalore (12610) on the 9th, 10th, and 16th of May will start from Katpadi instead of the Central Station.