PC Perspective published a review on the Crucial P1 500GB and 1TB M.2 NVMe SSD
A quote from the article:
Once we saw Intel launch QLC flash installed in their recent 660p M.2 part, I had a feeling that Micron would not be far behind, and that feeling has been confirmed with the launch of the Crucial P1 M.2 SSDs:Crucial P1 500GB and 1TB M.2 NVMe SSD Review
Both the 500GB and 1TB models are single sided. The 2TB (not yet released) will likely have packages installed at the rear.