Transfer in case of third year

How much km it is from your principal work place
if more than 50 km then you can
you have to fill the transfer form 109 with duly signed by your ca
as well as you have to write a letter in plain paper
including the name of cawhere's you want to do your articles ship with self attested copy of proof
after the form are submitted by both the ca your transfer and joining happened

Yes I'm shifting from Mumbai to Patna .... any other proof is required....?? and can my current principal deny from signing the form bcoz of due dates and workload

Any other proof in your words means???
he will not deny if you tell and show him the reason

I mean residential proof or dad's business occupation proof

Residential proof enough

But sometimes ca requirements different talk to your ca and check the list as well as per the form