> Rei was "created" out of the salvaged remains of Yui from Eva-01.
> Yui was only absorbed in 2004. In 2010 Rei-001 was said to be
> 5 when she was killed by Naoko Akagi. (which cues into when
> the salvage operation on Eva-01 was supposed to take place, in
> 2005. That make the "entity" known as "Rei" around 10 in 2015.
> In that there has been a Rei since 2005-ish.

That's assuming that all the Reis are the exact same age.  We really
don't know anything about the cloning process to determine if all the
Reis are the same age, or whether during the "memory transfer"
operation or whatnot, they're brought up to speed chronologically.

I think Rei is too much of an X-Factor to reliably use her as a
constant.