The answer to why Ant-Man closes out Phase 2 could lie in a recent rumour regarding Ant-Mans placement in the MCUs chronology. A new rumor has surfaced that says Ant-Man doesnt tactually take place after Age of Ultron, but rather concurrently. Once it was announced that Hank Pym wouldnt create Ultron, fans wondered just how Ant-Man would tie into the rest of the MCU, but there is a theory regarding a Pym/Ultron connection, and if it proves true, then having Ant-Man and Age of Ultron occur simultaneously would make sense. With these two movies taking place, it would make Ant-Man perhaps the most connective of all Marvels solo movies yet. Especially if another rumor holds true
Percival Constantine is the author of several novels and short stories, including the Vanguard superhero series, and regularly writes and comments on movies, comics, and other pop culture. More information can be found at his website, PercivalConstantine.com