The oil that separates in natural peanut butter

Oil in natural/organic peanut butter will commonly separate to the top, especially in warm weather. Would it be correct to assume that this oil is predominantly polyunsaturated?

No. Peanut Oil

Depending on why you’re asking, it may be worth noting that the polyunsaturated fatty acids in peanut oil are still appreciable (~32%) and they are almost entirely omega-6 fatty acids with minimal omega-3s.

Since n-6 and n-3 fatty acids compete for the same enzymes, a higher n-6 intake will result in reduced conversion of short-chain ALA to long-chain DHA and EPA.