Macbook Retina screen black coating issue

My MBP Retina 13" -Oct '13 has developed a discolouration of the black screen coating on the top left and bottom left sides. It is visible in bright light/sunlight and seems that the black colour is wearing off. I have been extremely careful about periodic cleaning and use a Moshi Teraglove sometimes with a little water sprayed on it. From the time of purchase, I have used the MBP in a BookBook case also purchased from the Apple store.

It is possible that this has happened gradually but became more noticeable now when I saw it under bright light/sunlight.

In normal light it is hardly noticeable but one can see it if one looks for it.

Now I can't help looking at it all the time. Am very concerned that this can happen to a MBP just over a year old and very carefully maintained. My Late '08 MB 13" Aluminium also has a black coated screen and is still in perfect shape!

Will welcome any suggestions.

Shankar