Hi Tanuja,
For Ptax sap will not release any type of notes for changes, you have to configure after confirmation of the local governance Ptax office (you can ask the same to your HR user in that particular Area). and accordingly you have to change the deduction amounts in the tables and transport to the production.
This is general practice only. do customizing as per the user data and test it in all the cases and take the confirmation from the user and transport it to the production.
Ptax deduction is every 6 months once for these personnel areas.
Best Regards,
Praneeth kumar