Very interesting timing that they canceled the news conference. To me it means there's nothing new to report at the moment but they are close to a breakthrough so buying time to have (as Winker likes to say) "the investigative team aggressively pursue the lead".
I also think it's smart to cancel if they were just going to do a rehash of the last two press conferences which told us nothing. They have to know that the next one needs to lead to something of substance if they are going to keep the MSM and general public interested and looking, calling in tips, etc. Not saying that's right, it's just how it is.