Where do our spirits go between incarnations and densities?

[Seeker of the One]

Where do we go between incarnations or let's say between harvest to another density? Also, do we incarnate in 4th density and above only once per density unlike 3rd density where we can incarnate multiple times?

I think this is a complex concept since I never seen Ra talking about it and I think they imply all spirits belong to some density in the creation, therefore if entity exists it might occupy some density for sure. What about internal planes of Earth? Is it astral 3rd density or what?