For anyone reading this, if you have the option of enabling auto-debit (which means you have a savings account with the same bank) then close your eyes and enable it. It has only pluses and no negatives.
I shall clear the 2 biggest misconceptions people have about auto-debit -
1. If you have auto-debit enabled and you pay via another mechanism (CRED, PayTM etc), there will be duplicate / double payment to your CC - This happens if and only if if your payment via other mechanism has not cleared and takes a few days to post. CRED always posts instantly. PayTM and Mobikwik are also mostly instant . Google Pay, Amazon Pay, HDFC BillPay can take even up to 5 days in worst cases. If you are not one of those people who pay on due date or just a day before, then you have nothing to fear. Another important point here - if the CC bill is Rs 1L and you have paid only Rs 90k, auto-debit will only debit Rs 10k.
2. The bank will add random charges to your CC and since you have auto-debit enabled you will end up paying for them - Auto-debit happens on the due-date. You will have nearly 3 weeks to review your CC statement for any random charges to dispute them.
Why you should do enable auto-debit?
1. Everyone will have unexpected life problems. Someone in the family may suddenly end up in a hospital. You might have a major setback at work or a sleepless project you are working on or personal problems that distract you for days. In that case paying your CC bill might be the last thing on your mind. Auto-debit will rescue you from interest / late payment charges.
2. On rare occasions, there are glitches with the other payment mechanisms like CRED, Mobikwik. Your money has been debited but it doesn't get posted to your CC due to a glitch on their end. I have had Rs 7k of a CC payment stuck in Mobikwik's black hole for nearly 6 months once. You may also have a situation where you have a huge CC bill and you have paid from multiple sources to maximize scratchcards/cashback. It is easy to make a calculation mistake (I did once and I cost me heavily). Auto-debit will again come to your rescue.
A downside that every CC user should be aware of -
If your CC bill is of Rs 2L and you paid Rs 1.9L by the due date, then the interest will be charged not on Rs 2L - 1.9L = Rs 10k but on the entire Rs 2L.