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Unless a major in new release is required for a prototype project. Then its a headache one has to accept. 
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It depends on how “major” of a we are talking, but often developers choose to stay on a stable release but “cherry-pick” code from a future version of UE4. Because you guys have of code, you can mash-up your own release however you want. We can even help you locate relevant commits in some cases.
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