If you are disciplined enough and do not spend money if you see it in your bank account, then there is no point of changing the bill generation date. To be on the safe side, pay bill atleast 7 days before last day of payment so that even if you pay using 3rd party apps and if at all payment fails, you will still have time to pay it.I have a hdfc credit card statement generation date on 12th of every month. Please tell me should i change it to other date like 1st or 2nd of every month and when should i pay the bill after generation of statement.