Family inheretance partition

Respected sir...
Can I  ask a  legal query? which would be of great help for my cousin.

A person Mr. Atul jointly holds and enjoys his and his unmarried brother, Mr.Balu's share of partitioned ancestral property. This is kept as property of Mr. Atul and his deceased unmarried brother, Mr.Balu... JOINTLY   ----- Schedule A
They have another brother Mr. kalip, Who was given another proper share by way of cash and movable things in this partition.  --- Schedule B

The partition deed was registered during 1959 or so..
Mr.Balu (unmarried brother) died in 1966.

Both Mr. Atul and Mr. kalip were all married and have family and children.

Both Mr.Atul and Mr.Kalip are not alive now.

The joint property comprises of land with house and 2 small shops (which is given for megere rent )and some paddy field. Family of Mr. Atul stays in the house for all these years and getting the rent form shops and enjoying paddy field also which is having fish farming.

Mr. kalip's family and children is interested in getting  their right share in the Mr. Balu's property.
Family of Mr.kalip  like to get share of land as well as all the previous incomes enjoyed from the joint property (paddy cultivation, shrimp farming incomes etc.,)

Can the family of Mr. Atul deny any share or property or share of income they were enjoying so far without any claim for the last 48 years? They are telling that nobody had claimed for the last 48 years.

Is Mr. Atul's family blound to give all the previous incomes by way of paddy and fish farming ?

Because Mr. Atul's family not interested to give any share, what is the possibility of Mr. kalip's family to get share of property?
Is any criminal or civil suit to be filed to get the partition and all the incomes so far? If they file a suit, normally how long it takes to get it partitioned?

If Mr. kalip's Family go to file a suit to get the partition done for their share in Balu's property, how long it will take to get final decree that is from lower court to supreme court? Also will Mr. kalip's family get the share of all incomes that Mr Atul enjoyed for the last 48 years?

Mr. Atul's family plans to do some repair work in their this dwelling house. Can Mr. kalip's family get a stay not to do any work on the house?

Also it is learnt that one of the shops is getting vaccated soon. So Can Mr. kalip's family get a stay from not allowing mr. Atul's family from giving the shop to a new tenant?

hope the respected expert can clear my doubts..

Thanks and regards...