It's not LCD pressure points if it's moving around and sounds like a hardware issue with the display itself. Here is what I suggest: take pictures of the whole screen showing when the areas have, as you described them, reappeared in a different area. I actually think it's not a backlighting issue or software/driver issue but perhaps a deficiency in the liquid crystal display itself.
I've seen this before but definitely not to this profound extent and most IT technicians would be understandably skeptical. By having pictures showing clearly it disappears and reappears in different places though that would tend to eliminate any accidental damage. Of course, this only matters if you are still in warranty. I would definitely check your warranty status by running your serial number here: http://checkcoverage.apple.com.
If you are still warranty I'd give Apple a call right away and report the issue, and even submit the pictures to the support specialist, and get a case number. This is important such that if it takes some time for the spots to reappear elsewhere you want to be mindful about when your warranty expires and try to bring it in before then. Hopefully these spots change position right away because, as I said, any technician at the Apple Store is going to be very skeptical that it's not accidental/physical damage as you are saying it's not.