Since there was no movement in the area with the demon king and the floating corrupted city, this allowed everyone to begin moving sooner than later.
Reports about the battle with Envy had already gone out to Genesis and the angel's leaders. This in turn had brought information back to the party. There were already celebrations and even some people saying that it would be best to push everyone back toward the floating city to eliminate it.
What that would do, would surely be a failure. Those people were not those that were taking the front lines. They Were the inexperienced or the desk warriors. Those who just wanted to get rid of a problem on paper and had no idea how to handle the physical side of the issue. Let alone the magical side.
Luckily, plenty of people were around to deal with those kinds of people. Many of the leaders of each race were already acting and explaining the future goals.