Went to Mumbai PSK to renew. APO ( PSK In charge) was very polite and mentioned they are in no rush ro start it in Mumbai. He said those epassports cause a lot of glitches in their systems and it will be chaos as he will have to refer people to RPO BKC office if they can't process them at PSK.

For my own renewal, since my current passport was issued in US, they were not able to locate the file in their system, so I was refered to RPO (and tatkaal was hence denied but still had to pay the fee for it).