For anyone in the UK looking for an OCI re issue ( over 50 / children etc ) the process seems to be very quick nowadays.
My friend applied for a OCI reissue for his son ( new passport ) and he got the re issued OCI in around a week .
mrs.ukdoctor appied for her first OCI and got her original documents back in around a week and got the OCI around 3 weeks later. Not bad considering that she had applied the week before Christmas.
Also for the UK the process has been changed for both new OCI and re issue
They take all original documents at the time of initial application ( unfortunately you or close family member has to go in person) and they send the original docs back in a few days and then send the OCI in a separate envelope once its processed.
In the old process you had to make a second visit to give your British passport once oci was granted but now the OCi is sent to you via royal mail/courier when ready .