GPA property issue

Hi My friend had buy a house on GPA approx near about 30 years ago. The orignal allottee execute GPA. Now the Orignal allottee put a tenant and take a portion of house on rent by taking my friend in faith ( my friend didn't sign a rent agreement with said person). After that The orignal allottee give a legal notice to that tenant that said tenant notp aying the rent. On this My friend put a court case where tenant said that he taken house portion on rent from original allotted not from my friend. later on case withdrawn by saying that he received rent (Orignal allotted said that he received rent from the tenant). My friend talks with his lawyer, he said we can wait for completing 30 years, he is said it will help in the case. Now my question is (1.) is there any law in which 30 years completing of GPA gives any favor to my friend side. if yes plz provide where can i download that law? (2) Now allottee and tenant are together how my friend can take action against them? (3) THe tenant didnt live there but putting his few things/items in a room and locked it, how can my friend vacate that portion that frauded teannt?