The upcoming Optane products will get a considerable speed boost, as Intel will switch from the PCIe Gen X2 interface to the Gen 3 X4 one. There will be a new M15 caching module, a new stand-alone 815P SSD and a new H10 combo module that will feature caching and QLC NAND storage. All these new products should be launched in Q2 2019.
https://www.notebookcheck.net/Next-gen-Intel-Optane-memory-modules-coming-in-Q2-2019.393121.0.html