Your subscription comes with an aggregate of 12,000/18,000/24,000/30,000 kms (as per your selection) per year of subscription, and you can carry forward the unused KMs for consumption until the end of subscription tenure.
In case the usage at the end of the subscription tenure exceeds the selected KMs limit + the carried forward KMs (if any) from previous years, then the excess KMs usage would be chargeable @INR 7 per km.