Marie - I've got everything crossed for you!!

I can't wait to hear.
Hey Jersey, cycle buddy! Excited you get to start a fresh new IUI cycle today.
So I posted about this in my journal, but last month I came in for monitoring on CD 11, and had 2 follicles, 22mm and 25mm and was obviously ready to trigger. If anything, I'm wondering if I should have gone in earlier, and triggered earlier. From everything I've read, most RE's trigger a clomid cycle once the follicles are 18 mm or bigger.
The nurse has told me to come in on CD 12 this cycle for US. This is one day later than last month. I'm nervous my follicles will be too big. I told her I came in on CD 11 last month, but she didn't believe me (!!) - she had my cycle dates wrong. I corrected her on my cycle dates, but she still thinks I should come in on CD 12...
Does anyone know what the upper limit is on a desirable follicle size for a clomid/IUI cycle??
I'm hoping the Doctor calls me back so I can ask him what day I should really come in...