They can’t take additional time to deal with new substantive issues, because there is an arbitrary schedule already announced! You don’t upend an arbitrary schedule for an assault allegation and a potential outright lie by a nominee about it. You just can’t, if you are upholding a well-established standard of sordidness. And besides, they don’t even know what happened, and there is no way to undertake an investigation. The FBI can’t investigate it, because it doesn’t investigate things. It’s not as though it’s called the Federal Bureau of INVESTIGATION. It’s now called the FBWTW — the Federal Bureau of Whatever Trump Wants — or will be called that soon enough. Whenever Trump gets an attorney general who will do as he is told.