Version and licensing model!

I really like the Unreal Engine, but also with the engine do some things yourself. I now have a question, Unreal Engine route will be closed source Unreal Engine during the future development of it? Or cancel this order can download the source code of the model, because I think this could make everybody can study. And now according to this update rate, 4.3 unreal or illusory 5.0.0 update to the back of his illusory of May? Is there a special format unification, such as cryengine canceled version, just called cryengine. Or kind of like autodesk, one version each year, such as ue2014, ue2015 …

Your questions are very hard to understand----the source code for UE4 is available for download if you are a subscriber, once your subscription period is over then you can no longer access the source online. You can still continue to use what you have downloaded however.
For the time being, Unreal Engine will continue to receive updates rather than whole new versions.

In fact, I just want to know, unreal began this order the open source model from the fourth generation, future will be closed source. Because I was a developer, I think have the source code to better study!

As long as it’s successful for Epic to have it open source then I’m sure they will continue that way.

There some exceptions as Epic not always can work publicly. Epic makes hidden branch when they develop some secret features, like Metal support, where obviously Epic could’t spoil Apple’s announcement.