Dear John,
Omshanti. Bro. Andrey has given a good reply. I would only like to add that Shankar is a mixed role where 'Sh' refers to 'Shiv', 'ka' refers to 'Krishna' and 'r' refers to 'Ram'. So, three souls are acting through the body of Shankar. The Supreme Father Shiv is represented as the Shivnetra, i.e. the third eye; the soul of Krishna is depicted as the half moon and the body belongs to the soul of Ram.
So, Brahma Baba, i.e. the soul of Krishna has been studying the Advanced Knowledge since 1976 through the body of Shankar living in the Subtle Region, i.e. a world of Brahmins in a stage of subtle thinking and churning. Subtle Region does not actually exist somewhere beyond this physical atmosphere/universe. It exists here in this world for those souls who are in a subtle stage of thinking and churning.
With warm wishes,
On Godly service,
Arjun