Through a situation I won't waste your time explaining, I now have both a tourist visa and a non-b in my passport.

Both have a validity date until October 20.

Is it possible to enter on the tourist visa today, then in 2 months exit and reenter on the non-b? Or does entering on the tourist visa nullify the non-b?

Thanks.

I think that if immigration spot it they will cancel 1 of them and stamp you in on the other.

So better off just using the non-b now than risk losing it I suppose. Hmm...