If an OCI does everything as per the rules, then s/he only gets a tourist sim that expires after 3 months. The legal workaround is that a friend/relative gets a line for you and lets you use the SIM card. If you find an outlet that will set up an account for you and not enforce all the rules you are lucky. Sadly these are few and far between. I nurse my late mothers post paid Vi account since the last 8 years at a cost of about 4000 Rs/year just to have a local number and plenty of data when I visit India twice a year for about a week each Last year when I came with the family I got my sons an airalo esim each for 6-7$. The elder sons iphone SE (2020) used it without issues on Jio, the younger ones iphone 12 mini would not recognize the network and didn't work. But that is probably an issue with his phone, it didn't work in the US last summer either.