One of the common analogies for the relationship between Big Mind and the human self is that of the ocean to the wave. They are one substance, and the wave is a local and temporary manifestation of the whole.
Sometimes, when people talk about it, they place the center of gravity in the wave even after it awakens as the ocean, as if the wave awakens to itself as the ocean.
But the wave doesn't awaken. If it appears to, it is just a preliminary awakening. It still sees itself as a unit, as an "I", and sense or taste or have an intuition of oneness with the ocean. The boundaries may blur and appear not so real anymore, but there is still a sense of I there, overlaid on the wave.
What really awakens is the ocean. It awakens to itself as the ocean, manifesting as that particular wave and all other waves. It realizes that it was only temporarily misidentified as a wave.
For the ocean identified as other local waves, it may appear as if that particular wave awakened. But it is always the ocean awakening to itself, and expressing it through that wave.
Whatever changes in the wave is just a reflection of the ocean awakening to itself while functioning through the wave.