I know several cases where the mutation of even litigation property was done within a month by Corporation. It gives the idea of the procedure.
One has to visit the Municipality / Corporation office, file the mutation applciation, with copy of the sale deed duly certified, with copy of no tax dues and pay the prescribed fees.
The time frame for any work with government authority as per citizen charter is 30 days. If there is undue delay, one can file RTI Application and seek information for the reasons on delay.
The authorities are not concerned into title of the person and will go through only document and mere mutation can not give any ownership rights to any party.