Anyone ever woken up from a dream, and found themselves able to move instantly. That's because that is exactly what the body is designed to do. This suggests that it is therefore quite possible to be in "sleep paralysis" and break out of it by wanting to.
If you can move whenever you want to there's no reason to assume that you had muscle atonia in the first place. Since you're making the claim that this is sleep paralysis rather than relaxation, it's up to you to provide the documentation for this claim.