Financing ended, car sold yet?

Hello forum, I have replaced the loan for my current vehicle prematurely last month. However, because of the notice period I still have to wait until the end of May until I get the letter from the bank. i.e. I transfer three installments again “normal” (March, April, May), and then end of May the whole rest. The following problem/the following question I have: On my current car (Honda Accord Tourer 2005) the brakes, the timing belts and a few other small repairs must be prepared I actually wanted to postpone this and put the car in payment or for a good used exchange. But if I get the letter in almost 2 months it will be almost too difficult for me to drive around like this. Is there the possibility to exchange the letter of the new vehicle at the bank for the old one? So that the almost two months still have the new letter as security? I don’t want to have more than 1000,- Euro in the Au I don’t want to be too “obtrusive” at a bank. The financing is running through the BMW bank. Maybe someone knows what is “growth”. Thank you very much, T. (YetAnotherUser)