Without being able to really offer a thorough diagnosis, it may seem to be electronics related rather than the actual panel itself with regards to the banding. Your technician would be able to address that more properly than I would be able to.

If the screen scores are staying up for just being displayed for a minute, it may be possible that your brightness/contrast settings are set too high, or are on "Dynamic". I would suggest seeing if turning down some of those settings would help.