kCFURLVolumeIsAutomountedKey missing, from Time Machine

when I launch mvim from the command line, then I am seeing messages throughout the day stream to the terminal that look like this:

2019-04-29 02:00:00.308 MacVim[25865:2008397] kCFURLVolumeIsAutomountedKey missing for file:///Volumes/ccc/: Error Domain=NSCocoaErrorDomain Code=257 "The file “ccc” couldn’t be opened because you don’t have permission to view it." UserInfo={NSURL=file:///Volumes/ccc/, NSFilePath=/Volumes/ccc, NSUnderlyingError=0x7fd205d05aa0 {Error Domain=NSPOSIXErrorDomain Code=13 "Permission denied"}}

2019-04-29 03:00:15.539 MacVim[25865:2016017] kCFURLVolumeIsAutomountedKey missing for file:///Volumes/timemachine/: Error Domain=NSCocoaErrorDomain Code=257 "The file “timemachine” couldn’t be opened because you don’t have permission to view it." UserInfo={NSURL=file:///Volumes/timemachine/, NSFilePath=/Volumes/timemachine, NSUnderlyingError=0x7fd2072289d0 {Error Domain=NSPOSIXErrorDomain Code=13 "Permission denied"}}

These seem to coincide time wise with when my Time Machine and/or Carbon Copy Cloner backups are timed to auto mount SMB shares in order to run backups. No idea why this would cause macvim to complain. I don't remember this happening before, but its quite annoying to have my terminal clutter up. Mvim seems to run ok otherwise.

Detailed steps to reproduce the behavior:

1. Run mvim from the command line
2. Wait for Timemachine to run a backup over network

Vim Version 8.1.950
OSX sierra 10.12.6

Start by running mvim from the command line on macOS Sierra and reproducing the warning when Time Machine or Carbon Copy Cloner mounts the SMB backup shares. Trace which MacVim entry point emits the kCFURLVolumeIsAutomountedKey message and determine what behavior should change without affecting normal use. Done means the repeated terminal warnings no longer appear during backup mounts while mvim continues to run normally.