I don't think that you have to necessarily go the full-time early college entrance route. The child could attend university for specific classes, in this case higher math. Ania's son is doing this (she posted about it on the college subforum).
Clarification - DS did audit a Calc 1 course over 7 weeks of last summer. He completed pre-calc as an 8th grader and now as a HS freshman he is in AP Calc BC at the HS. Problem will start next year as he will have to take classes for credit at the local U. This is going to be a logistical nightmare as we live 35 miles away from his HS and even further away from the U. Furthermore, my understanding is that as a sophomore he will have to have a full load of classes at the HS, meaning he will be taking math at the U on top of it. Honestly, I am not looking forward to it. Looking back I wish my kid had done number theory or counting/probability in 6 and 7 grades respectively.
Someone said that it is a good problem to have and those college classes will certainly look good on his college application. i agree, but it still looks nightmarish...
As for the OP question - please do look at the colleges your kid might be interested in attending. For the very selective colleges four years of math are required, even if you want to study Philosophy at HYP
Do not limit your choices early on.
Also, don't understand how Stats is not considered a math subject? What is it then???
