So, are those your systems? Or samplings from the project? I have an Ubuntu 18.04.4 host running a 1050 TI with no overclock and it's running WU's in 6800 seconds for me. I also need to get my Dual 750TI system configured to exclude one of the GPU's, because it looks like it's been running two at a time on just one of the GPU's. As mentioned elsewhere. But it looks like even that card was running around 12,400 seconds on singles, and 19,200 seconds on duals.
No clues or hints for OC though.