I had to go back and find a post by RaisinCharlie on another thread.
I'm not from NC and I'm honestly not familiar with anything a grand jury does except what I've seen on Websleuths.
RC said the gj and LE could keep a decision 'secret.' Or the defense attorney could also know. In other words, IF I understand it correctly, they could keep the fact they heard the case secret and the decision as well, until an arrest. So, yes they could make an arrest later this week, IF they heard the case.
Seems the more seasoned and local posters, well RC at least, don't believe this case has been heard yet by the gj. They think LE is still putting their info together. IF they're doing dna AND computer files and phone records, it's possible it could take a month or so.
We have to remember the person they're investigating is a computer expert of sorts, so LE needs to be a bit more diligent than normally is called for.
JMHO
fran