I finally had to dispute my HSBC balance. I was sick of in not updating to reflect a zero balance and HSBC was no help. I believe they A> report a month late and B> report either on or around the first of the month regardless of statement date (one rep told me on the 1st, the second at the end of the month).
It *is* the last business day of the month that reflects the balance. However, it's hard to know what is responsible for the delays, hsbc or equifax or what. I blame HSBC as I hear about so many problems with them.