Usually the Contract states: " This contract is contingent upon Buyer obtaining a loan ...
and then lists the terms of the loan: Loan amount, interest rate, term of the loan etc.
The dictionary meaning of "to Obtain" is "to get". Pre-approval, Underwriters approval or any sort of approval is NOT the same as "obtaining" a loan. . Even though less likely, but the underwriter are known come up with last minute urge of getting some new doc from the borrower: last bank statement, last pay-stub etc. etc. If for any reason the bank refuses your loan at the last minute, you may be one out 1000, but you may have miserable life. At that time you do not think of the probability of refusal of 1 out 1000, because you become 1 out 1.
The loan is "obtained" only when the loan is funded. Thus, I believe that the Contract language shall be that " The contract is contingent upon loan is funded ...."
Do not remove Loan Contingency until the escrow closes.