To avoid missed or late payments I recommend you do not use Quicken Bill Manager to initiate a payment transaction. Instead logon directly to the biller (the credit card website) and authorize them to direct debit (aka PAC Draft, Autopay, APS, etc.) the next and all future payments from your checking account. The biller will do all the work for you and make an electronic debit on the due date and you don't have to worry about being late.
In Quicken just record a scheduled reminder which does not execute as an online payment into your account register on or before the Due Date and before you download transactions from the bank or credit card containing the payment transaction. That will allow Quicken to match your register transaction to the downloaded data and not cause any further issues.
DexterB said: Unfortunately, this also prevents me from being able to download monthly statements, which is a nice feature, regardless of how I choose to actually pay the bill. (I like having the statements at my fingertips when I'm using Quicken.) I am paying more bills on the billers' websites now than I'm paying thru Quicken. Dexter