Sure even a physical place is temporary, even though it may last for years if it was made of rock or stone, like caves used by primitive human beings. But in some astral places one lives like my mother does and one has no idea that the place will be altered even though it will be.

One is mentally protected there because one has no ability to rate time. A similar condition is endured by us when we are infants where we feel that the earth was always here and that it is a solid something, and that we will be kids forever and our parents will be elderly people in the same way.