Index Grace Period
You've got a confirmed ticket on the 6 PM outstation local. The train may wait a few more minutes after 6 PM for passengers before departing to the next station. The extra time between the mentioned departure time and the actual departure time is the grace period.
In insurance, a grace period is a specific period of time during which an insurance policy remains in force even if the premium payment is overdue. This gives policyholders a little extra time to make their premium payments without losing coverage along with policy benefits.