Just did a clean 12.0-BETA2.1 install, minimal config to create a pool and enable SMB sharing, and ran into this issue with robocopy. Does not appear to be fixed.
Original file:
Created: November 23, 2017, 2:16:27 PM
Modified: June 9, 2017, 1:14:26 PM
Accessed: September 12, 2020, 5:27:05 PM
Copied file:
Created: January 1, 1980, 7:00:00 PM
Modified: June 9, 2017, 1:14:26 PM
Accessed: September 12, 2020, 5:27:05 PM
Each run of robocopy considers this and about 2,000 other files "Tweaked" because of this.