I was just in the forum and clicked on "see my TER reviews" next to a name and was taken to a screen that just said "Provider not found".

Obviously, my first guess is she's been delisted for some reason, but wondered if it could be related to the glitchy stuff that's been going on of late. Also, I would've guessed if someone got delisted their posts would come down too. Maybe not?

Although I've seen in rare cases posts being removed upon delisting. I expect that's a special request.  

Also delisting doesn't seem to automatically remove doubles reviews, although I know that can be done as I've seen it happen.

You can try searching for the provider in the Search Reviews page to see if she shows up there. If not, it's likely she's adios.

Delisting removes the provider's profile. Doubles profiles usually remain. All her old posts remain (unless they are removed for other reasons), but as a delisted provider she can't post any new posts.  

Even hobbyists who get banned still have all their old posts up. (And usually their reviews remain)

... their handles on the reviews are changed to something generic, i.e. an alphanumeric string. That's what I've observed, anyway

who still have all their old reviews and board posts up under the banned handles.  
However, I am not doubting what you say either. You know TER. There is always variation in the way they do things.  
Some things seem random. Others, I'm sure that have their reasons and we are just not aware of them.