AGB_FIRM patched, will I be okay with downgrading?

Hi, so currently I'm on 10.6 reinand on my new 3ds XL with a patched agb_firm that allows the installation of gba injects. I was wondering if it was possible still for me to downgrade to 2.1 and get my OTP and all that without risking a brick? I would rather not have to reflash 9.2 all over again since the otp process is already fairly time consuming.




Thanks.