Anything can be arguable if people choose to argue about it, but that does not make it true, or even reasonable. Creationism is not science.
Scientific theories do not become laws. We still talk about the theory of gravity, molecular theory, and germ theory etc. The difference between a scientific law and a scientific theory has nothing to do with the level of certainty. A scientific law is a simple concise statement that can be expressed as mathematical equation. A scientific theory is a broader explanation that explains a range of related observations. A scientific theory should be falsifiable, and it should make useful predictions. A scientific theory is not simply the best guess.
Yes, a scientific theory can be revised, or replaced if and when new observations warrant it. But a scientific law can also be revised or replaced if the observations warrant it.
Creationism does not qualify as a scientific theory. Evolution does.