You can only change taqlid from one living Mujtahid to another one if, after research, you are satisfied that the second Mujtahid is the most learned one (a'lam).
What are the conditions for switching marjas if the previous marja is still alive?
Question originally asked on
Aalim Network Archives https://www.al-islam.org/organizations/AalimNetwork/msg00726.html
Professor Liyakat Takim is the Sharjah Chair in Global Islam at McMaster University in Canada.