Airtel Static IP config in personal router

Hey,
I have airtel fiber.

1) How do you purchase static ip ? I dont see any option in Airtel thanks app
2) Is there any internet disruption after applying until route is configured ?
There is no option to purchase static IP from the application. You will need to email net@airtel.com. Airtel will send somebody to configure your router with Static IP. Once the Airtel engineer has configured, you can continue to use the static IP from the Airtel router, or you can take the IP details from the Airtel router and configure it in your own.

From my personal experience, Apart from the automated response, nobody bothered to reply. I had to raise a support ticket to Airtel citing the email to invoke an action. But send the email first, If you raise a support ticket directly, They will simply say, "Send an email to net@airtel.com"
 
From my personal experience, Apart from the automated response, nobody bothered to reply. I had to raise a support ticket to Airtel citing the email to invoke an action. But send the email first, If you raise a support ticket directly, They will simply say, "Send an email to net@airtel.com"
Seems i got lucky. They called me within few hours after sending email yesterday. And today engineers configured it and its done already. Engineers took a few hours from scheduled time and it was not clear whats happening but they configured everything from their side and did not enter my house.
Checked on few sites, and ip survives reboot and i can also see static ip configured in wan2 with wan0 deactivated ( which had pppoe). I am not using any additional routers.

So pretty fast.

Now have to see how billing works. I just pay for the whole year in one go for fiber but static ip cost is monthly.
Seems weird - prepaid + postpaid ? Hopefully i can pay more than bill to cover next bills.