I thought that was weird, too. But it looks like this is just the "web view" of an email newsletter they (Center for Advanced Hindsight) sent out. Website is here: http://advanced-hindsight.com/
In the US, and North Carolina specifically (where Duke University is located) it's still the 30th. So you're probably good. At least for another 3 hours (it's 2pm there now).
EST is shorter than Eastern and more easily recognizable than ET, which is a more heavily overloaded acronym. I'm sure it's used by people who are aware of the technical meaning and not forgetting. There's no quick and reliable way to refer to non-EDT EST during the non-daylight months without mentioning the absence of daylight savings time or specifying the UTC offset.
http://advanced-hindsight.com/startup-lab/
It seems we are running up against the deadline, probably should have posted this sooner.
Advanced hindsight is 20/20