Scored 525 with conceptual gaps you identified after the exam — that's actually a useful data point, not a disaster. It tells you something real about where you stand.
40 days is enough to move significantly if you're targeting weak concepts specifically. The biggest mistake I see is people doing more practice questions hoping the score will just go up. It won't unless you're learning from each one.
My suggestion: spend the first 10 days not doing timed practice at all. Go through your weak areas concept by concept. For Data Sufficiency, focus on understanding why something is sufficient, not just that it is. For Problem Solving, work on identifying the problem type in the first 20 seconds before you calculate anything.
Then do timed full sections in the last 3 weeks, with rigorous review after each. The review is where the score actually moves — not the practice itself.
Also look at your DI score specifically. A lot of people targeting 695 lose 20-30 points in Data Insights because they don't practice Graphs and Tables or Multi-Source Reasoning at all. If that's a gap for you, it's one of the faster things to fix with targeted practice.
You've got enough time. Just be deliberate about which concepts you're attacking each day.