Those who aren't getting JioCinema Premium with their JioFiber/AirFiber subscription, keep checking JioCinema app on your Jio STB.
I remember, in my case, when Jio included JioCinema Premium, a popup appeared and on clicking that it activated the subscription on my number.
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Finally Jio fixed the JioCinema subscription issue on my JioFiber connection.
A popup appeared and on clicking proceed, JioCinema Premium subscription got activated immediately.