Joint Account with 3 legal heirs.......

I m one of the three administrators cum legal heir in  the two Joint Accounts with BoI.

One for Savings Account and otherone for Demat Account. I m not the first holder in the accounts.

Is it possible to change my status from 2nd to 1st Holder in these accounts.

Assuming if it's possible what are the taxation liability of 1st Holder once all moneys and shares are distributed to the legal heirs as per family agreement.

Thanks.