M1 iPad Pro 11 inch case discoloration
Anyone else seen the aluminum back discolor like this:
iPad has been in a case since it was taken out of the box.
iPad Pro 11-inch Wi-Fi
It is difficult to determine what caused the discoloration just by looking at a picture. If I were to make an assumption, then the discoloration appears to be yellowish in color and getting darker at the bottom half. Did you have soft TPU (Plastic) case over the iPad? Clear soft TPU cases tend to discolor (Yellowish) as time elapses. That can transfer over to the back case of the device under ideal conditions. The other thing is dirt and grime can cause that discolored appearance.
The above is my opinion however if you get that iPad examined at the Apple Store, then they may be able to directly identify the cause of it.
Axel F.