Are the changes to the morphogenetic field permanent, so they could affect subsequent incarnations as well?

Once the changes are produced, they remain, and that is important because, as you can appreciate, the morphogenetic field is ever-present and continuing to provide the basic overarching energetic imprint to maintain the person in the physical during the course of their life. So while those alterations made to customize the current life experience are stable, they can be overridden, edited out, or replaced by a new set of characteristics for the next incarnation so as to be an optimal configuration for the next family grouping the person will be joining. The life circumstances might be quite varied between successive lives, with dramatic differences geographically, culturally, as well as with the agenda for the lifetime itself, given the new circumstances. While people can maintain a theme in a series of lifetimes as their life agenda of primary importance, they may choose to have quite varied circumstances as a way of gaining further life experience, as well as being in a position to influence many varied settings and situations by participating directly in what is taking place.