How often do creditorslenders report late payments to your credit report once twice a month?

Most creditor/clients of the CRA's report monthly via automated tapes. Some creditors report sporatically, some never report. Some only report when you are late, like utility companies.

Most creditors report on a 30 days cycle, but that isn't always the beginning or ending of the month. It will also take some time to report on your credit report. So probably you are looking at a 60 days turn around on most late payments.