xps 15 9560 screen colour problems

Just taken delivery of a new xps 15 9560 with the 4k UHD screen. The screen has inconsistent colour banding across it. On the left is a magenta hue and the right cyan hue. 

If I display a grey scale across the screen there are pink band of colour in the grey so not a smooth graduation.

I'm a photographer so this was noticeable straight away.

I spoke to Dell support who didn't seem to be bothered to provide any service and effectively said this is normal.

Only had the laptop a few days so considering returning for refund.

Is this normal?