Still Sheep and most not yet Born. They were still His and there names had already been written in the lambs book of life from the foundation of the world.
You cannot apply illustrations to anything except what is being illustrated without creating an error.
Jesus was using an illustration (a shepheard gathering sheep, sheep from another flock, one fold) to speak of the gathering of Gentiles.
You misapply illustrations but outright deny passages specifically defining "the elect".
That is what Calvinists have to do.
While their philosophy is "easy-believism" (so it is attractive to many), simple, and a logical philosophy within itself it is also a very interwoven philosophy. It builds on itself.
So if one point is wrong then the whole philosophy falls apart.
The Calvinist, when faced with a passage that challenges their philosophy, cannot re-examine or question that issue within Calvinism because it would negate their faith. They have to question Scripture and find a work-around (whether another passage they can use or a way to redefine Scripture).
Scripture defines "the elect" , solution is ignore it and misuse an illustration.
Christ is the Propitiation for the whole world's sin , solution is redefined "whole world"
God so loved the world - redefined "world"
God forgives based on repentance - find another way
God defines "death" as "returning to the ground, turning to dust" - turn to RCC doctrine
God will not ounish the righteous - make an exception
God recreates man - does not apply to redemption
The list goes on.
If you allow Scripture to dictate your faith then your faith falls.
So you allow your theory to dictate what Scripture "really" means.