This happened a few years ago while doing a mock check ride (in a slow Cessna 150), what would you have done? Situation: 8 miles East of a Class D airport (with radar), runway 26 in use. Upon initial call up I get " make straight in, Runway 26, report 3 mile final." I turn directly towards the airport. I call 3 mile final and get "cleared to land runway 26." 2 miles out the tower call and says "we gotta change things, Challenger jet is on an instrument approach behind you, landing clearance canceled, make right traffic runway 26." How do you join the pattern now?