This often happens after disputing. It's normal. Your FICO score probably took a hit with the new late, but your DOLA did not change. If you were to pull your original report directly from TU and/or EX, you'll likely find a drop off date (some CC accts don't have this though). So as long as that date didn't change, meaning it doesn't say 2015, then you are OK. Otherwise it was improperly re-aged.
I can't speak to HSBC, but if you were to offer a PFD, they might accept it and you could get it removed. If it is your oldest account, then you might want to reconsider ever doing a PFD and pay them without it. You can actually lose points by removing and old, unpaid CO.