First, I would ask her to show you exactly where in the ASRM guidelines this is required. I have never been able to find these posted online (please, if you know, tell me), so I doubt whether you'll be able to independently verify this. Second, does your clinic have an explicit age limit? I wonder whether they're thinking of adopting one and she's trying to push you into a cycle before they do that. I would ask her that point-blank. That might explain the mysteriousness of her actions; she doesn't want to scare you away from this cycle by being honest that they plan to impose an age limit.
I would also ask her point-blank whether they are getting pressure from their insurance provider to impose age limits. And then, if you can't get satisfaction, much work as you've put into this, I'd really think about going elsewhere, because if this cycle fails, are they going to allow you to cycle again?
Maggie (in VA)