transfer of OCI sticker to new passport while living in India

[puremeteor]

Folks,
Has anyone here gone through the experience of transferring the OCI sticker from the old passport to the new passport in India (I am looking to get this done for my 2.5 year old son who already has an OCI card but in his old passport).

If so can you please share info on the following points

1. I presume this can be done at the FRRO offices. I am from Mumbai but I'll be moving to Bangalore straight after entering India, so planning to get this done in Bangalore.

2. Would like to get an idea on how long it takes to get done.

3. Do they need proof of address (presume not)

4. Any idea about the documentation etc.

Thanks in advance.