The Dreamliner recently released for FSX can be updated with the first hotfix by QualityWings.
They plan to address their 787 issues to make it a stable product first. Only then, the work will move to prepare a P3D V4 product release.
There will be an upgrade plan from FSX to P3D v4 : 50% off the P3D v4 price for FSX customers, for two months only.