It is. The disk is mounted at /mounts/00d6c142-ca89-4f65-93d0-dd74f14236f8

It does have a permanent mount point, this is the line in /etc/fstab:

UUID=00d6c142-ca89-4f65-93d0-dd74f14236f8 /mounts/00d6c142-ca89-4f65-93d0-dd74f14236f8 ext4  defaults,noatime 0 1

This is an NVMe SSD, AHCI is only for SATA.

I looked and couldn’t find any settings for disks being hotswappable, and it hasn’t happened on any other distros i’ve tried on this system, so I don’t think this is it.