help! with assuming loan

Good afternoon,

I have an epa for a home in CA. My question is about making pmts on a loan, not notifying the mortgage co about “assuming” the loan, and dealing with the due on sale clause. Would a quitclaim deed be filed if you are taking over pmts and not officially assuming the mortgage? If so, when? In doing this, what happens if the owner opts to file bankruptcy while I own the home and have not yet flipped it?

Please help. Thanks!