Can we apply for OCI together with Surrender certificate?BLS also accepts passport surrender applications at 40 Gillingham. I surrendered mine there last month. They recommend to go to 60 Gillingham if you are applying for the Indian visa too with the surrender application.
Surrender certificate takes less then 8 weeks for sure. Consider approximate timeline around 4-5 weeks. People have received their well before 4 weeks too.
One of the requirement for the OCI now is to produce a surrender certificate and Cancelled Indian passport. You can apply for your wife's surrender application and your OCI application at the same time at 40 Gillingham and then apply for your wife's OCI once she receives the surrender certificate and Cancelled passport.