Partnership - death of partner

Dear All good morning, 

One of our Client Firm, there are two partners( A &  B). last month 3rd week of December 2014 one partner Mr A. deceased. 4 legel persons are there ( C, D, E & F).

now my Doubt is 

Old Partnership firm still now business operating.

1. Any Due date is there for legal heirs enter into partnership deed, if yes means, Section number?

2. Stamp Paper Purchased 4th week of Jan 2015, therefore, when New Legal heirs enter i.e., Date of deceased  partner or   Today date.

thanks & Regards

RNB