rsync log file contains spurious info

[neverdimed]

sometimes rsync's log file indicates that files were updated, eg deleted, and then the next day i run rsync and it wants to make the same changes that it claims were made the day before. I keep an accumulating log - every time i run rsync the log file is updated; so the contradiction is easily seen in this file (it says the file was deleted from the drive and now it wants to delete it again, and the file is still on the drive). I think this tends to happen when i sync to an external drive and then almost immediately disconnect the drive. Would there be a lag like this, ie the log file would be generated and rsync would complete but the updates are not fully realised?

re "I have done a search for similar discussions": it's difficult to search for this, I'm unsure how to word it