Is ~710 your goal? That is, are you within striking range now? Or are you looking for more?
Did you take those practice tests under 100% official conditions, including essay and IR? (I want to make sure that the numbers we're looking at are valid.)
What kinds of timing problems do you have? (Note that I don't ask whether you have timing problems. Everyone has timing problems. :)
If you're not sure, use this article to analyze your most recent MGMAT CAT:
http://www.manhattangmat.com/blog/index ... ice-tests/If you'd like, you can also come back here to tell us the results of your analysis and what you think you should do based on that analysis. We'll tell you whether we agree and advise you further. (Note: do share an analysis with us, not just the raw data. Part of getting better is developing your ability to analyze your results - figure out what they mean and what you think you should do about them!)
If your quant is fluctuating from 44 to 47, one possible culprit could be the timing - if you can even that out, then you'll be more likely to hit at the top end of the range than the bottom.
Use these two articles to help with timing:
http://www.manhattangmat.com/blog/index ... to-win-it/http://www.manhattangmat.com/blog/index ... nt-part-1/Finally, it sounds like you don't have a hard deadline - that was what was making it difficult for you to stay motivated and why you booked yourself a test date. 3 weeks is not a ton of time, so I just want to say: aim for that date, but about 7-10 days out, take a practice test (under 100% official conditions) and give yourself the flexibility to say, "Hmm, I need a few more weeks" if you think that's really warranted.
As long as you reschedule >7 days in advance, you only have to pay a $50 fee to reschedule. Now, that's still $50, so that should keep you motivated to try to hit your original date. But if you really do think you could benefit from a few more weeks, then suck it up and pay the $50. :)