Say doctrine A claims premise X to be true, and Y to be false.
Say doctrine B claims premises X and Y to be true.
There is some sense (I believe; you might want to confirm), in which the "burden of proof" is tilted to the side of B. This is, there is no "responsibility" for individuals in A to justify "why Y is not true" (or at least lower than that of individuals in B in justifying Y).
Now, let us add a temporal dimension.
Let us say that first, it was doctrine B. Then, a rupture appeared, whereas a group of individuals denied Y. Thus appeared doctrine A.
Given this temporal structure, is it now the "burden of proof" tilted towards the side of A? In a sense, they rejected Y, thereby giving origin to the second doctrine. Is this the case if we focus only on the individuals belonging to A and B (i.e. those who believe in X), without requiring them to prove to the rest of the world that actually, X is true?
Is this analysis of a philosophical school? Does this analysis has a name? How can I approach this question from a philosophical point of view? Any reference is more than welcomed.
PS: Behind this abstract question, lays an analysis of the history of Christianty, whereby Reformation emerged primarily as a negation of many Catholic doctrines. I think the question itself is independent of this background, but it might be informative to give it anyway.
PS2: I hope tags are well selected. Please change if not the case.