Demise of a co-owner

Dear Experts,

If the Co-Owner of a Jointly Owned Flat in Maharashtra Passes away after Executing a Duly Registered Will in Favour of his/her Co-Owner, then Will the Index II as well as the Share Certificates of the Society both Reflect only the Name of the surviving sole Co-Owner thereafter on Submission of requisite Documents to the Corporation  & Society concerned respectively or will the Names of both Co-owners still be Cited on the Index II as well as Share Certificates even after the Demise of the Co-Owner?

Thanks,

Kaushik.