I think that the reality is:
EMH for on-site guests will be going away, whether in October or in the not too distant future, to make way for selling the park again, at regular intervals, at night.
My guess is that you'll end up with two flavors of "after hours":
- Normal "after hours" events which is just you buying a ticket to be in the park in the evening
- "Special Holiday/Event Parties" which already exist but will be an even greater up charge than the normal after hours nights.
At this point it seems like the writing is on the wall for this. From WDW's point of view they get to sell the park again when they otherwise would have just kept it open so all of those daily ticket sales effectively get doubled.
I'd also expect to see the "early morning entry" deals just become an everyday occurrence. Want to enjoy the park in the morning for a few hours? It's another ticket. This one won't multiply their ticket sales by 2x but I bet they get 50% or so more out of it just by offering it.
To be fair: the whole EMH deal was to entice people to stay on property. If the rooms are filling up as-is there's no reason to offer it any longer AND they've already successfully experimented with selling the park multiple times a day.