Also in case it matters for anyone, here are system details on the laptop containing the SDSSDA240G drive that was having the problem described in the previous message.
HP Pavilion x360 - Model 11-n010dx. Newest BIOS and UEFI (I had updated those first)
Sandisk SSD Plus SDSSDA240G - Firmware Z22000RL
Windows 10 Version 10.0.14393 - 64 Bit
Standard SATA AHCI Controller version 10.0.14393.206
Microsoft Storage Spaces Controller version 10.0.14393.206