If Kerala (20MP ) gets a separate Zone then Tamilnadu ( 40 MP with Puducherry UT ) needs 2 zones in Chennai and Madurai/Trichy
Chennai zone with the existing Chennai,Salem and a new Puducherry division.
Madurai / Trichy zone with the existing Trichy and Madurai division and new Tirunelveli division.
Thiruvananthapuram Zone ( 20 MP )...
more... with the existing Thiruvananthapuram and Palakkad division and new Kannur/ Caulicut division.