Are you referring to
those specs? If so: No, the SSD in the adapter will use the PCIe interface, just like with the
T570.
The second SSD in the WWAN slot can either be a Cache drive or a storage drive. The 2242 form-factor isn't nearly as prevalent as 2280 M.2 for sure, though I think I have recently read that some PCIe NVMe SSDs will be released in this smaller size.