They are:
- The Desperate Hours 6k? (US and CA)
- Hellraiser Quartet of Doom 4k (UK)
- Hellraiser Quartet of Doom (UK)
- The House by the Cemetery 4k (UK)
- The House by the Cemetery (UK)
- The Iron Fisted Monk (US and CA)
- Witness 4k (US and CA)
- Witness (US and CA)
Tech specs: Blu-ray.com (although they seem to have copied and pasted some details from the 4k to the 2k without adjusting)
How many times is Hellraiser going to be released? Is this the first time in 4K?
There was a German 4k. There often is, the Germans are often ahead of the curve with fancy home video releases.