The release notes (https://developers.google.com/glass/release-notes) only go up to 18.1 so I assume 18.11 may just include some bug fixes, but would be curious to know if anyone has any ideas about this.
I've only been using it for an hour or 2 since getting 18.11 but so far it's been smooth and stable without any reboots (which were happening for me prior to this update).