Whether 2AC ticket got downgraded to 3A? Whether it happens? Yes it happens sometimes due to technical reasons or due to unavailability of the coach
Rules & Refund
1. There is rule that states that tickets can be downgraded
2.Difference between 2AC and 3AC ticket can be got by filing TDR
TDR can be filed by choosing a option which says “Difference of fare between the booked class and lower travelled class” after travelling.
Once TDR is filed you will get the money back directly into your account or card through which you have booked your ticket