The New and Everlasting Covenant

Many people are surprised to find out that the covenant didn't start with abraham. The point of the covenant is to put us in a relationship where we can have god continue to work with us, however long that takes to bring us back to him. In mortality, it's first given to adam and eve as they leave the garden of eden. And so it is a an everlasting covenant. We really enter into that covenant at baptism. But as you said, it was so it was established in pre mortality.