IUI- follicle scan & success

I was diagnosed with PCOS and my left tube is completed blocked. After trying for two years, three rounds of clomid, and a chemical pregnancy, we were told to move onto a specialist.

We started a medicated <a href="https://glowing.com/glow-fertility-program">IUI</a> a few weeks ago. On CD 4-8 I took letrozole 5mg. Yesterday, I had a Menopur 150 shot. This morning was my follicle scan. Due to the size of my follicles, they said to continue Menopur today and tomorrow and go back Wednesday morning for another scan.

I’m not sure what to expect since this is my first <a href="https://glowing.com/glow-fertility-program">IUI</a> cycle. Do follicles typically grow that fast?

Has anyone had success with this type of protocol? I will also have a trigger shot (ovidrel) and progesterone suppository.