The letter states "referred to the fact that the FBI had completed it's investigation". Then the letter states "I agreed that the FBI should take appropriate investigative steps designed to allow.... whether they contain classified information".
In plain English, the case was closed, but now there is new evidence and we're investigating it. Sounds like 're-opening' to me.
They are in fact re-opening so they can ammend the findings. If it is determined that new emails warrant charges, she may be charged.
The real news story here is that this is what everyone will be talking about for the next weekend, that's three days, with a response by her on Monday. So, maybe four days. That's more than 30% of the remaining election cycle.
I was under the impression that there's some operational distinction between looking at and evaluating some information, and declaring a formal, targeted investigation as "open". But its probably too fine a distinction for the general public to be bothered about. It's a bad look vs a worse look.
Perhaps, I think the key takeaway for Americans is the "Not Guilty" that Americans seemed to believe was the case in regards to these emails (It was really "Nobody would prosecute") may not be so.
Perhaps it would have been better to admit fault and deal with this outright in the beginning, rather than attempting to manipulate the process[0].