You can't use flash storage for reliable unpowered archival. It degrades (gates leak electrons) over time, unlike magnetic storage. This is also unpredictable,

You can't use flash storage for reliable unpowered archival. It degrades (gates leak electrons) over time, unlike magnetic storage. This is also unpredictable, as reliability depends on both operating and power-off temperatures, as well as existing wear. See: https://www.anandtech.com/show/9248/the-truth-about-ssd-data-retention https://www.anandtech.com/show/9248/the-truth-about-ssd-data...