Hi @David_Razorsek, it will take some time. According to our tests, depending on VM size and file system structure (blocks allocation) it may take up to a week with 3-4 hours daily VM uptime.
I can't say that there are something like typical results, it all depends on VM file system data structure. Within these three weeks do you install any software, updated Windows? We have updated the KB with instructions to free up Mac disk space: https://kb.parallels.com/en/123553
Check if you have old Windows installation.