Steps to reproduce:
1. Open User's attached project
2. Build and Run on iOS
3. Notice: Scene 1 looks okay
4. Wait 10 seconds. Notice: Scene 2 appears

Result: Scene 2 looks stretched.

Reproduced with: 5.6.0f3.
Not reproduced with: 5.6.1p1 (fixed).

Tested with: iPhone 6S iOS10.3.1

Note:
The first scene is simple, with a few visual elements and a basic camera. The second mostly the same, but with a simplistic script which uses OnRenderImage() to apply a sort of "do nothing" effect. (It reads the color of the source and writes that to the destination.)