User blog comment:Mckrongs/Monster Hunter Frontier Season Forward 3/@comment-4677839-20120124055204/@comment-87.217.44.109-20120124145612

Both teams are separate and they have a contract that doesn't allow Frontier devs to use monsters from the main series beyond Unite. In addition, the main team cannot use Frontier monsters past season 1.5. That's because Frontier is shared with another company.