You could not study at B University until your change of status was approved and in effect. If you would like to begin your studies sooner rather than later, you would need to depart the country, apply for an F-1 visa, and re-enter the country using that visa. You can read more about student visas at http://myattorneyusa.com/student-visas.
Answered on May 27th, 2016 at 3:27 AM