Hi wso123123,
Your post provides a lot of information, but it's missing some information that will help me to offer you the specific advice that you're looking for. I'll have a few questions at the end of this post that will help to clarify exactly what you need as you continue to study.
To start, we should look at your Official GMAT Scores: 500, 560, 540, 480.
GMAC has publicly stated that a Test Taker's Official Score is within ABOUT +/- 30 points of actual ability. This is important to think about, since ALL of your GMAT scores hover around 520 +/- 40 points. These results imply that you treated the Official GMAT in just about the same way (overall) every time you took it (+/- a few correct answers). Whatever you did during your studies, when you faced the Official GMAT, you did certain thinks consistently well, but you made the same consistent mistakes.
Second, it appears that you scored higher on a number of your practice CATs, but we have to take a good look at HOW you took those CATs:
When you took your CATs:
1) Did you take the ENTIRE CAT (including the Essay and IR sections)?
2) Did you take them at home?
3) Did you take them at the same time of day as your Official GMAT?
4) Did you ever do ANYTHING during your CATs that you couldn't do on Test Day (pause the CAT, skip sections, take longer breaks, etc.)?
5) Did you ever take a CAT more than once?
If you took your CATs in ANY ways that significantly deviated from how you took the Official GMAT, then your practice CAT scores would likely be 'off' and you wouldn't even realize it.
Third, there's also the matter of HOW you were studying right before you took each GMAT. Studying 12 hours a day is NEVER a good idea. If you were studying in that type of volume in the week leading up to each of your Official GMATs, then you likely 'burned out' right before Test Day - and you were likely too tired to perform at a higher level when it mattered the most.
As far as how you should proceed from here, I'd like to know a bit more about your goals and overall plans:
1) What is your score goal?
2) Are there any other Schools besides LBS that you're considering (and what are their application deadlines)?
3) Are you now planning to apply to LBS in the Fall, 2016?
4) What were your Quant and Verbal Scaled Scores on each of your Official GMATs?
Thankfully, the GMAT is a predictable, standardized Test, so you CAN train to score at a higher level.
GMAT assassins aren't born, they're made,
Rich