The laws of physics are not centralized as governments, currency or google code / github, that aside they can and most probably are incomplete or expressed in a way that only applies to certain constraints (size, time, theory of relativity comes to mind)

The laws of physics aren't really laws at all, but rather the best guesses humans have for describing physical processes.

There are also more than one set of laws, and they're not all compatible with each other, which is why efforts are being made to provide a unified set of laws.

https://en.wikipedia.org/wiki/Theory_of_everything

Mindless pedantry.

I think those are what determines permanency. But let's not be pedantic.

the laws of physics change each time our understanding does

Right. That's why we never find out we were wrong about anything in science.

The laws of physics aren't interchangeable with our understanding of them

And in that case, maybe our understanding that there are laws of physics and that they don't change is false.

That's a philosophically naive view of how science works.

Claiming that our understanding of science 500 years ago is at all equitable to the way science works in 2016 is even more naive.

That's the opposite of what I'm claiming so maybe you should work on your reading rather than science. Our understanding changed over 500 years. And in another 500 years some moron will be saying the same thing you are, that we've always had perfect and final knowledge of science, and it will be just as stupid then.