However, two year courses (e.g. two year IB HL courses, or AP physics 1 + AP physics 2) may not cover all of the topics of the SAT subject test after just the first year. They may go much deeper than one year regular high school courses in the topics that they do cover, though.
So a student taking a two year course in 11th and 12th grades may find that s/he is not optimally prepared for the SAT subject test at the end of 11th grade, unless s/he previously had a one year regular high school course in the subject (but then s/he could have taken the SAT subject test at the end of that course).