In one of Guru's plays, a great spiritual Master is depicted having a conversation with God prior to his earthly descent. The dialogue between the Master and God has all the sweetness of a discussion between a father and son, and they share many illumining and precious secrets.
A disciple once asked Guru, in the late nineties, if he had a similar conversation with God before he took human incarnation. He said that yes he had, but that it was strictly confidential and top secret, and he couldn't share it.
Somehow, I think Guru's book "My Yogi-Friends, my Avatar-Friends" might give us a few clues as to what he and the Supreme might have discussed. It's a truly cosmic book!