You could put a script in /usr/lib/systemd/systemd-sleep which execute hdparm. And you can use hdparm with /dev/disk/by-uuid/ instead of /dev/sda...
Or try to use /bin/sh -c "/bin/hdparm -B 200 /dev/disk/by-uuid/XY"
You could put a script in /usr/lib/systemd/systemd-sleep which execute hdparm. And you can use hdparm with /dev/disk/by-uuid/ instead of /dev/sda...
Or try to use /bin/sh -c "/bin/hdparm -B 200 /dev/disk/by-uuid/XY"