In DV-2013 for example, there was a message on the Entry Status Check website that instructed applicants to check again at a specific date as more entries might be selected; is there any such message now?
Keep in mind that when an application is made, the dependent (spouse and children) information is also collected. Those 50K visas cover the principal applicants and derivatives. May be, this year they cut the process short once they found out that the winners have more than usual number of dependents ( just a thought, not a fact). What I am trying to get at is, the 84K number does not necessarily imply an additional drawing, especially in the absence of a "check back as there may be more selections" type of message.