I doubt this will remain leak proof until show time.
It's very true. It could leak. So what is the risk of participating a conference or submitting a journal paper to editor/reviewers/organizer from the legality point of view? It could be interpreted as the company giving non-public information to selected few. In addition the presentation itself is behind a paywall (CTAD). In 10/15 PR, TGD already stated the PDD results were good (stat sig/clinic sig/safe) but without data. So data is/will be non-public unless the company makes another PR prior to the presentation.
"Something important washed over those in control to warrant this kind of change in a key spot"
Absolutely!!!
I don't think the CTAD would have made the number of exceptions (results from a PD trial, LB after the LB deadline, out of sequence LBs'), if the data wasn't truly profound. I bet we will see positive responses from ALL trial participants.