Well, she's got family in the business who would have advised her well :) Yes, she does own them but for the foreseeable (probably at least 10 years) she's licensed those rights to Polydor, and they actually control them for that period.
This is great! Can't wait to see her perform it live. I gave my High Expectations vinyl a spin last night and it is a really strong debut. Looking forward to what she does next.