Run an AppleScript daily with launchd
One shouldn't include the .plist extension when starting a launchtl process directly. Your command should read, instead, launchctl start local.SkeletonBow.EjectAllDrivesAt8

Also, the launchctl man pages indicate one shouldn't use leading zeroes when setting Calendar start time. The content should be &lt;integer&gt;8&lt;/integer&gt; and &lt;integer&gt;0&lt;/integer&gt; for the Hour and Minute keys.

Keep in mind, too, that when using CalendarInterval (as opposed to an elapsed-time Interval) to set a launch time for a process, that if the machine should unexpectedly be asleep at 8:00AM and therefore be unable to initiate the process, it will initiate the process upon awakening. That does not happen when the time setting is interval based.