Mild PCOS

I've always had regular periods + positive opk + biphasic bbt trend, but a recent transvaginal ultrasound showed signs of PCOS. The only symptom is scanty periods, mine last for 2.5 to 3 days. This came as a surprise to me since all signs pointed to ovulatory cycles.

Is it possible to have a dominant follicle + biphasic bbt trend and still not ovulate?

I've been prescribed 2.5mg of Letrozole for Day 3-7.

We've been TTC for 1 year now so hopefully this will help this cycle.