The Psyche (book), Reincarnation and Contact Report 109 Part3

For approximately every 100 years of life you live out on earth, the spiritform needs about 152 years in the beyond. [4] As a result of overpopulation, a new consciousness and new personality can incarnate with the reincarnation of the spiritform a short time after death, for example a half an hour later. Such cases are very rare, even with overpopulation, however it bears mentioning that in such cases the new personality has to cope with the chronicles from the storage banks, because such individuals receive strong impulses of remembrances of the earlier personality. This happens because there wasn't enough time in between incarnations, and there is still a strong connection to the material existence. 

After death, the spirit-form and consciousness-block pass over into their respective levels in order to process the accumulated data. I will omit the process of the spirit-form, although this naturally is just as important, because the spirit-form determines the exact time-point of the incarnation of the consciousness-block, though in some ways its different processes, as I see it, are easier to understand.