But that "card dealing" and storage of said cards requires the conscious act of doing so, which requires a conscious being. It's a very odd and backwards way of looking at reality, where everything is "pre-planned". This simply is not so. If it were, and say your "time" is November 12th 2016, then before that time you'd be able to walk in front of a speeding train or jump off a cliff - whatever - and you would not die. No, events play out as they will in a completely natural way. It's nature all the way down.
Don't think about it that way. Your physical being is pretty much wired from birth. Not to say you can't choose build a mighty body or choose to transform yourself into a replica of a concentration camp refugee. Or whatever.
But could it be that genetically you're pretty much pre-wired for things like your skin, your largest organ, being unable to maintain it tone and you wrinkle? Your joints beginning to deteriorate regardless of use or abuse?
Your various systems seem to maintain for only so long and they all begin to deteriorate according to principles at this juncture unknown to science. If they are known, they're keeping it a pretty good secret. Regardless of how well or how poorly you take care of yourself this deterioration seems inevitable.
The point being that for any given person there's not some doomsday date recorded in a celestial ledger but perhaps your deterioration and final collapse is inherent in your makeup. You might maximize your stay by taking care of yourself and it might make for a more comfortable journey as well. But are you going to be able to reset your own personal time-clock?