There are many people here who know more about this stuff than I do, but here goes.
From what I understand, BPD moods are impacted more from outside influences, and tend to change quicker than BP.

I've read that therapy is better for BPD, that there aren't really meds for BPD. But I read it online, so who knows if it's true.

Also, I've heard most people sort of "grow out" of BPD as they age. Meanwhile, BP is for life.

Take care.