No, I know that, I'm well aware of the uses of drugs like metformin in PCOS management, - but metformin wasn't ever designed to act on the menstrual cycle, so there's no set of definite outcomes or effects. Some people get nothing out of metformin at all, be it regular or XR, high dose or low dose. Whether someone has insulin resistance or not doesn't change the fact that it's what metformin is designed to do - address insulin resistance. The Pill was designed to prevent pregnancy, that was it's sole purpose. Yes it can help with PMDD, skin problems etc. but HBC wasn't designed for that purpose.

The pill - you know that's going to always automatically override cycling, prevent pregnancy etc. because that's what it was designed specifically for.
Met doesn't have that advantage because although it can affect menstrual cycles, that wasn't it's original function. Sure there's some available data now (as opposed to 13 years ago when I started it) but there's always going to be more data available (or even just anecdotal evidence) when talking about the purpose a drug was designed for, rather than an off-label usage.

All I'm trying to point out is that there is no set guide to what happens when, unlike there is with drugs designed for cycle regulation/hormonal imbalances, her endo/gyno should've explained all of that.