I cannot think why jean being here will stop adult jean from resurrecting as iceman and beast not to mention cyclops are all existing with their counterparts from the past. If the Phoenix wasn't after her to transform her into its host but just to burn her/imprison her in the astral plane or wherever what is it thinking will it achieve in regard to getting back adult jean? is it trying to force her to come from the after realm to stop it from running amok and killing/imprisoning her younger self if it isn't alt version? Why would it bother to travel all this way to burn her up when she is just existing in her own niche and totally ignore hope who dispersed it the last time it came? that seems to point out that it considers teen jean as a aberration it won't abide though why it thinks so is anyone's guess. Will it ultimately come to the reemergence of pheonx five or phalanx if all the former hosts divide it and absorb its essence though admittedly it isn't likely given the resurrection of jean grey.