Since it is a 95% purchase and you are only putting down 5% the bank monst likey will not eliminate that mortgage insurance on your loan. It has been my experience in the past where you will have to have it for a certain amount of time. However once that time lapses all you have to do is contact one of your banks approved appraisers get the house appraised and submit it to that lender. Im surprised it came in that high 20% higher? So all the comps on the appraisal are very much similar and close to your property? If so you must have gotten a hands down steal. But talk to your lender to see what he knows of off hand. Let me know if you need anything else.
Incidentally the reason we got such a good deal on it is that it was an estate sale. It had previously been listed for closer to what it appraised for. The house has some odd "old lady" type of features, and the kitchen hasn't been renovated. I imagine that they weren't getting any bites so they dropped the asking price by a lot. We put a contract on it a few days after they reduced the asking price.
Since you haven't closed yet, why not talk with your lender to see what your options might be.