You go here and you deal with it
Not quite what I meant. Little information about the event, as it is currently being reviewed in great detail, may be available.
That is during the conceptual part Krusty, frankly, the scenarios I most enjoyed had very detailed plans and a great deal of effort into the training of those plans.
Right now, it doesn't take a master planned battle to attract a CO and players. When the event is underway, there had better be a great deal of planning.
As for the last 15 minutes, again, to my point. If the CO can team build, draw players, attract team mates, involve them in the event from the onset, they will draw a nearly full field during the event. That, again, is up to both the CO to draw the players and the CMs to provide a stable event condition so that the COs can count on there efforts not being wasted.
If the CO changes his orders around at the last minute, does not involve the players, keeps them clueless and uninformed and uninvolved, you can guarantee the same return on game day. Lack of enthusiasm and participation.
If the CMs do the same by changing things up at the last minute, they will reap the same rewards as well. Hence the stability on our end allowing for the immersion on yours.