Splitting a paper into two papers?
It is unclear to me how you intent to split the papers.


If both theorems are in field A, there seems to be no need to split them.
Having the theorems in one paper, and the background in another, seems illogical.


From what I read, it seems to me it should be one paper.

If however you have in mind a reasonable way to split the result into two cohesive and self-contained papers, please clarify so we can better understand the situation.