i highly doubt this, ishgard is clearly something tie with heavenward, then why have a "battle of ishgard" into a 2.x patch? more seriously, you can't bring a story out of nowhere. they are building the arrival of the 3.x (and possibly the 4.x already with the new emperor). the fact that we have seen a ashien next to the archibishop was clearly for point that the next story will be there.

all of this for say, the 2.5 part 1 will probably the end of the story that still going like omega arma, the decision of nanamo and the end of the plot of the small rascal hehe