I haven't seen reliable stats which would confirm your assertion at all about the bluck of the home school and Christian school people being categorized as post millenial.
that's an honest gotcha. i was talking on the basis of my personal experience, personal conversations, rather than citing any rigorous statistics. as a rule, home-schooling families tend to be more thoughtful, deliberate, and savvy than their moloch-feeding peers. therefore, more likely to be post-mil calvinists. otoh, many christian schools are started by pre-mil baptist congregations, whose efforts i salute.