Things get weirder as their get clearer, and more complex as they get simpler. The thing about metaphorically putting one toe in the water before fully entering an incarnation with full frontal awareness, is getting more and more relevant. Of course I can't recall pre-physical memories easily once inside, as can no one who didn't specifically train for this, or inherited a body by walk-in, which was previously trained for this.

How early does a person actually enter with full awareness into their body? I recall scenes, individual scenes from being very little, but it's really only those, before it truns a more continuous experience of flowing time. Maybe I wasn't actually present all along, but have no way of knowing how much of my memories are merely filled in NPC auto when I wasn't there.

Using secondary incarnations "backwards in time" in timelines that are already registered as "complete" in the akashic records, is another possibility I wasn't aware of. It appears that as long as the karmic outcome and all societal interactions follow the principal structure which is already set by surrounding events, some things can be left open even after the planet officially ended. So it's still possible to find what is currently NPC lifetimes in Earth history and enter those to live there for experience and skill gaining. Using the method of isolating a soul shard and then sending it there, letting your subconscious have those experiences as an externalized tulpa, is a great method of dealing with things that weren't solved yet. 

However, another possibility appears: what if such an sub-conscious shard is sent back to say Atlantis, and gains immortality there, staying all along into modern days, or the timeline is so persistent that the karma to be solved is still there now, then it may lead to actually, at some point finishing this lifetime here, only to jump back to 40 000 years ago and spend all that time from there to here in physical reality to fill in those experiences that were missing, possibly also attracting other souls to enter with you along the way. What would the experience really then be like, knowing that the new Earth already exists, but in 40 000 years from now'' ?

That's an interesting concept.