This is all my pure speculation but I was thinking Cold Harbor was trying to stuff Gemma's personality back into her body. That flash at the end of Ep1 looked strangely like brain waves and we know that the numbers are intuited based on how they make you feel and placed into emotion boxes.
What if Gemma was pulled from the crash brain dead, but severing her into Ms Casey allowed her to have an innie life? And that's why she seemed strangely devoid of emotions and so scared to go down the elevator and be "turned off" back to her vegetative state? And that's why Mark is so important, because who would be more in tune with her personality than her husband, even if he isn't conscious about it?
Then of course you could ask questions about why Lumon would want this technology and what Eagan they want to revive but I digress...
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If you wake up at a different time, in a different place, could you wake up as a different person? #theresafreakingghostafterus