on one hand the announcement was likely to made before trade...

on one hand the announcement was likely to made before trade commences on the 15th as per the trading halt announcement
on the 13th later in the day from when the halt was called he states to one individual working hard tonight to try and surprise the market which it did do by making an announcement on the 14th.
A lawyer should understand the meaning of words and how they are constructed have certain impacts. By stating surprise in my mind this opens up more questions as to what was known at that point in time than a few hours earlier and also questions how many times has this happened in the past. .
Yes there is an embargo for 20 minutes once a announcement is made but for those that felt it was likely to occur on the 15th they could have been surprised (pun unintended) to see it come out a day earlier unless they were watching the market intently. Not all investors can sit infront of a computer screen for the full trading session..