Yeah i just opened my bnet and check this out, you are 100% correct,

I have multiple wows on my bnet and for each wow i have a classic wow options

BUT on my new bnet i only have 2 wow accounts and it seems i only have 2 wow classic options

so yeah, technically if you multibox wow current expansion then you could multibox classic wow.

mmmmmmmmmmmmmm i wonder if it will be worth it multiboxing wow classic?

dont they strip many of the stuff that made life so MUCH easier