#1 is feasible in that it's no different in applying to multiple B-schools. You'll pick one and tell the other you won't be attending.
#2 probably won't work. Getting into each individually and trying to convert may raise the question as to why you didn't apply to the joint program, especially when some schools like Kellogg have a single application that is reviewed by both schools.
Don't have a comment on #3, but #4 goes back to the point that if you're filling out a joint application, it may be one application and you can't tailor it to one school or the other.
Hope this helped!
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