G.2:
I just found this link:
http://wwp.greenwichmeantime.com/time-zone/usa/eastern-time/
This is an online clock showing the time (in real time) which I am guessing most of the CDO competitions refer to.
Maybe this clock (the code at least) can be incorporated into the website somewhere, as the “official” time keeping device.
Just for the record I am GMT+10, which usually means I am about 15 hours in front of the competition, which translates to, I have a 15 hour “buffer” before I can HAVE to submit my entry.