Well, Jettison 1.8 didn’t go quite as planned. It adopted a different system API to get power notifications so that it could better handle “dark wake” events, where macOS wakes up briefly to perform backups and network maintenance while it’s sleeping. While the dark wake stuff all worked as expected, it ended up causing issues with some external drives not getting ejected before sleep because sleep notifications were delivered slightly later in the going-to-sleep sequence. It didn’t make a difference on test machines here or with our beta testers, but impacted some users out in the real world once version 1.8 was released. If you’re one of those folks, I’m sorry for the trouble 🙁
Version 1.8.1 was released today, and takes a hybrid approach, using both the old and new API’s to ensure that it gets sleep notifications as early as possible. This restores the reliability of Jettison’s eject-on-sleep capabilities.
This release also allows you to turn off the feature introduced in version 1.8 that quits Music, iTunes and Photos before sleep (to allow ejection of external media containing music and photo libraries). Apparently iTunes doesn’t correctly return to the same location in audiobooks when Jettison relaunches it after waking up, which can be really annoying. So you can disable the feature by using this command in Terminal:
defaults write com.stclairsoft.Jettison leaveAppsRunning 1
As usual, full release notes and download links are on the Jettison release page.