A 70-100 point increase in 5-6 weeks is possible, but it will take some work.
It sounds like your test-taking skills (namely time management and endurance) are holding you back. So, you'll need to keep working on these.
In the future, complete the AWA section as well. This will help build your stamina.

If you're interested, we have a free GMAT time management video at https://www.gmatprepnow.com/module/gener ... es?id=1244

Cheers,
Brent

From this point on in the Guide (Day 44), you will take frequent FULL-LENGTH practice tests and carefully analyze them afterwards. During this analysis, there are four main types of weakness to watch out for:
1. specific Quant skills/concepts (e.g., algebra, standard deviation, etc.)
2. specific Verbal skills/concepts (e.g., verb tenses, assumption CR questions, etc.)
3. test-taking skills (time management, endurance, anxiety etc.)
4. silly mistakes

For the first two weaknesses, the fix is pretty straightforward. Learn the concept/skill and find some practice questions to strengthen that weakness. The OG Verbal review is a good resource but it's hard to work on specific question types/topics. To focus on one topic at a time, you can use BTG's tagging feature to isolate one concept. For example, here are all of the questions tagged as statistics questions: https://www.beatthegmat.com/forums/tags/ ... statistics
See the left side of that linked page for more tag options like verb tense, comparisons, etc.

I've already touched on building your test-taking skills.

Finally, if silly mistakes are hurting your score, then it's important that you identify and categorize these mistakes so that, during tests, you can easily spot situations in which you're prone to making errors. I write about this and other strategies in the following article for BTG: https://www.beatthegmat.com/mba/2012/09/ ... n-the-gmat

As far as how long it takes to reach your target score, that varies from student to student. However, once you take a few more practice tests, you'll have a better idea of your score trajectory.

I hope that helps.

Cheers,
Brent