How do I go about using this? Do I start with completing the syllabus and do drills simultaneously?

I am consistently not finishing the LG section when I take timed PT. I've been having 6-7 questions I do not get to before time runs out. However, when I BR I get a -0 on LG. Should I continue studying LG with the goal of increasing my speed to take the June exam? Or, do I just give up on LG and focus my attention on RC and LR and wait for the August Exam?