Using the Subtract Time part of Timestamp Adjustment causes 2 errors: 1) the time is added instead of subtracted in the new file, and 2) the timestamp of many (but not all for some reason) of the original files are changed. In my case, photos from 2016 now say 2021. I can't find a way to undo this-thankfully I have backups. I will be updating to the newest version and trying again, will update this report after This has happened twice, when trying to subtract 3 hrs from my photos (2493 items). No issue when adding 3 hrs. Will do more experiments if updating to the newest version does not help and will update the thread.
Fixed with Bug 515679 Maik
One more question: do you use the Time Adjust Tool within BQM or the standalone tool outside of it? In BQM, Time Adjust must always be used as the last tool; otherwise, date changes by other tools in the queue are possible. Maik