It's heading for Hope as she's already hosted the Phoenix force1.
During the final confrontation with Bastion, Hope turns into what appears to be the Phoenix and blasts Bastion as Wolverine, Colossus, and Emma watch shocked.
It's also after Omega-level psionic mutants, we know this because of how the Phoneix force came back after it's first visit to earth2
The Phoenix Force returned to Earth when it felt the mind of a human transcend the physical realm, a mind that resonated with the Phoenix Force's energy. A young Jean Grey had telepathically linked her mind to her dying friend, Annie Richards, to keep Annie's soul from moving to the afterlife. In doing so, Jean's mind was being dragged along to the "other side" with Annie.
It also has an attachment to the Summers and Grey family line, with the majority of it's hosts/victims being part of that line. (To wit, Jean Grey, Rachel Summers, Madyline Pryor, and Scott Summers from memory).
My speculative thoughts are that due to Hope being the figurative embodiment of mutant-kinds re-birth, and her ability to mimic Omega Level Psionic powers and the connotations of her surname (whether through actual relation or assumed relation by other mutants, and thus psychically felt) all make her a primary host for the Phoenix Entity.
2X-Men Vol. 1 #101