SAT/SAT Subject Test Problems

Have a slight problem. Right now, stuck with a 1960 on SAT and want to raise it 2100> by December SAT’s. I’m not sure whether to continue taking SAT’s until I reach my goal and then take subject tests or take my 3 subject tests this June & have it over with then take the SAT’s from next October onto December. Which one would benefit me more/be more manageable and why?