Honestly, I'm in a similar situation, and different people will tell you different things. In general, if you start at a higher point, your scores are less likely to improve. In general, if you don't understand concepts, but you memorized all the random details from FA, your scores are likely to plateau at a lower point. In general, if you spend a lot of time on quality studying, especially targeting your weaknesses, your scores are likely to improve more.
I think what you should do is to not focus so much on how many points you're going to improve. Look at your weaknesses, look at your strengths, study the hardest and the best you can for the next six weeks (or however long you have), and when you take the exam(s) again, that will be how much you improve. It means absolutely nothing if I sit here and tell you I went from a 200 to 250 in a month, or that this other guy studied for 2 months and got only from a 200 to 220. Neither of these anecdotes will help you in the slightest bit because you're not them, and what happened to these people won't necessarily happen to you.