Unreal Engine and its EULA

So I’m trying to decide what a good, long term option is for indie game development. Basically, I’m wondering if I should focus my attention on learning and programming with Unreal engine, developing all future games on it’s platform. Or if I should just program and develop my own games from scratch (I understand doing things from scratch means it will take much longer for me to actually produce a product, but again I’m trying to think long term, as in 10-20 years in the future). Part of my decision it based on how license agreements typically work. My questions are:

I know right now Unreal engine has a license agreement for which you can basically develop and distribute your games to the public for a 5% royalty (paid to epic). But Epic can change this license agreement at any time correct? If so, does that mean I might only owe 5% today but could very well owe 10% tomorrow if Epic decides to do so? What if they decide their engine should no longer be openly distributed and wants their source code to be kept private again so they can go back to the old model of licensing out for large sums of money. Would this mean no one can then distribute any of their games without paying a large up-front fee? If so, what would the chances be of something like the above scenarios happening?

Basically just trying to get a better grasp of EULA’s and specifically how they could effect indie game developers.

Here’s the relevant portion of the EULA:

They can change the terms at any time and you will receive notice that there are new terms if you try to use your account, if you don’t accept them then you won’t be able to use the launcher or source access (and therefore unable to download the engine again) but the terms you originally agreed to still apply.
For what you’re concerned with, it wouldn’t likely happen with UE4, if they have a big change like making it more expensive in some way or getting rid of source access then that would be in a completely new version like UE5. In that situation they would likely stop providing access to UE4 (like they have done with UDK) but that would be a long ways off, UE4 will have a much longer life than UE3 since they have much more control over the source and it’s something they plan on building onto for a very long time.

Thanks for the reply. So then it sounds like if they did change the agreement and say stopped providing access to ue4 source, you could still develop and distribute your game using an older version of the engine at the 5% royalty fee (as long as that was the contract at the time) correct?

If they do something bad, there will be cryengine as alternative. Its too c++ engine. Cryengine is probably best way to go but for me it lack tutorials and maybe ue will have more features in foture.

Yes, thats correct.