Can any one change the Marja e Taqleed in between if example I was in Taqleed of Agha Ayathulla Khominee after his Death I have changed to Agha Ayathulla Sistani so can any change the marjae Taqleed or not

we have 3 ways
1- marja who in life was aalam from marja who died, in this sitvation you have to change taqleed from die to live
2- marja who die was aalam from live, in this place you cant change the taqleed
3- both of them same in this place also you can change the taqleed