Even I priorize the digging skill for a Dup. It do all the trip to a excavation site to dig just one block and go away leaving the rest of the job for another Dup do the same **** until finishes. In the pic below we see the bug happening and the Dup leaving the site.
How I use to do to fix?
"!" alert prioritizing the exavation.
What I hope as a fix for this problem:
The dup high lvl of excavation clear all the blocks until the end.