Anticipated bounce in score with utilization decrease from 38 to 27%?

[Anonymous]

I've been working paying off some legacy grad school credit card debt, and have decreased my utilization substantially over the past few months.  My report indicates that amount owed and % utilization are my two biggest problems.  Otherwise, my credit history is perfect (AAoA is 9 yrs; total history is 15 yrs; no late payments whatsoever, no negatives).  Right now, I'm sitting at 733 EQ and 732 TU.  I would very much like to bump up to >740 in the next two months to qualify for the most favorable terms on a home loan.  My plan is to apply for the mortgage late summer (in two to three months).  I'm told by my lender that I easily qualify for nearly the top rates for conventional loans, given my other financial factors (income, employment).  But 8 points doesn't seem that hard to acheive, and the balances need to get paid anyway.  

So, this month, I made payments to decrease overall utilization to 27% (down from 38% last month).  I have 12 total accounts: three loans (car, student, personal) and 9 cards, of which 5 have balances.  No recent inquiries.  One card is utilized heavily at 50% (it has a 0% APR that I'm taking advantage of until December); the rest will be down to 30 to 35%.

I know that this will improve my score.  But, I'm wondering by about how much and within what time frame.    I utilized the FICO simulator, which provided a range of 733 to 757 for my circumstances.  So, all else continuing as is, decreasing my utiliztion by 11% could possibly leave me at the same score?  That doesn't make any sense.  Should I estimate within the middle of that range, at about 745?

So, I'm hoping that others with experience might have some insight into what I could reasonably expect from my plan.

Thanks.

P.S.  I know some will say pay off all debt before even considering a mortgage.  I understand that logic.  However, my lender has also warned (and I believe him) that given current trends in lending, it will become harder to obtain loans without 20% down and scores upwards of 760 will be necessary.  For first time buyers, that's just a killer.  So, my gut is telling me that this summer is my time.  My long term budget plan calls for paying off all remaining debt within 12 months of home purchase (while still contributing 10% monthly to savings and full amont to an IRA). 

[Anonymous]

If you can get your debt to credit ratio to 15% or atleast under 25%, you will see the dump almost imed. In your position paying everything off to 0 makes no really sense. Leave some of that cash for your down payment. When buying a home, you need credit , but also CASH!. From experience, if you tease your creditors with low amounts owed, that pushes them to increase your amounts in hope you will spend more. But don't! But yet, use that to your advantage because the more they increase your credit lines, that in itself will drop your debt owed to your credit availaboe thus again making it easier for you to pay less to them and show more cash at time of your mortgage application.