Curiously, the M1 Macs don't support Hibernation at all. The feature has been dropped. (run `pmset -g cap`, you’ll see that hibernatemode and hibernatefile have

Curiously, the M1 Macs don't support Hibernation at all. The feature has been dropped. (run `pmset -g cap`, you’ll see that hibernatemode and hibernatefile have disappeared.) Regarding your troubles, I'm not really surprised that it's not working with a third-party SSD, and it definitely sounds like a hibernation glitch. Have you tried disabling hibernation altogether? disable: `sudo pmset -a hibernatemode 0` re-enable: `sudo pmset -a hibernatemode 3` (in fact, if my admittedly poor memory serves, I think I busted hibernation mode on my old 2009 17" MBP doing the same thing, and this trick fixed sleep…)