To be clear, you mean Aug 30, but what the hey. Unfortunately there is no time limit for covering. "Days to Cover" sounds like a time restriction, but it's "the number of mean daily volume days required to cover the outstanding shares short."

The shorts have been gradually working VDSC down - and up - and (mostly) down again. Their percentage gains increase the lower they can short, manipulate, bash the PPS down. So they have the best of both worlds ... increasingly good gains in BOTH directions ... which aren't available to the average retail investor.