Words and names have meanings. Adam means "mankind:.
Does 'man' mean a man and his wife? Assuming Adam and Eve are both alive for the 1,000 year period are they married any longer?
M't:22:30:
For in the resurrection they neither marry,
nor are given in marriage,
but are as the angels of God in heaven.
The 'consequences' of that is it is a static population that is 'the flock' during that period of time and the only 'perfected people' people are the 24 elders. They are the OT Prophets that were resurrected on the same day Jesus was and they are the 24 elders in the temple from Re:4. That temple is the same one Daniel would have had his prayers heard in and it came into effect in 70AD (Luke:21:4) when the temple in Jerusalem is dismantled. I tend to think the 24 are from before the flood and the 12 oldest men are there as are their wives. In the 2,000 years they have been there there have been no children born to them but on earth they had many children so they are taking on the role that 'grandparents' take on and they are educating their children on how to raise a child. They have almost 1,000 years each to 'observe' how raising children and what can go wrong when you are the least important people alive. I would imagine their children that are not named all died at the age of 120. (Isaiah:65 has that age as when a person is given immortality, the perfect heart is already there when they take their first breath). That would be the 'pain God gave Eve as the price of her sin for believing a lie. Satan did correctly say that she (and Adam) would become like the 'sons of God' once she knew about good and evil. The lie was they they would not enter the grave as punishment, pain would be seeing most of her children enter the grave before she did, Adam had an unhappy wife and the price of being 'one flesh' is Adam would not leave her side no matter what, even if it meant dying. Their flock for the 1,000 years is all the ones referenced in Re:20:4 and that is basically the 12 Tribes going back Abraham's children, the Church are the Gentiles that were taught beginning 3 1/2 years after the cross (Acts:10) They are taught during that time so they have perfected hearts and can survive judgement of the 'sons of God' from Ge:6 when Satan and the remaining fallen angels are released and they come against Jerusalem as it would have looked if sin had never taken place. Able's offering is the one that is acceptable starting with 45 days from the day the 7th trump sounds. Zec:14 is how that takes place 1,000 times before the time Satan is released during the Feast of the Trumps.
This is the part of the Church that was promised they could gain immortality without going to the grave. The whole of the ones alive are referenced as 'servants' in Isiah:65 and the Jerusalem mentioned after those few verses is new Jerusalem after it lands on the new earth.
Zec:13:8:
And it shall come to pass,
that in all the land,
saith the LORD,
two parts therein shall be cut off and die;
but the third shall be left therein.
Zec:13:9:
And I will bring the third part through the fire,
and will refine them as silver is refined,
and will try them as gold is tried:
they shall call on my name,
and I will hear them:
I will say,
It is my people:
and they shall say,
The LORD is my God.
Zec:14:16:
And it shall come to pass,
that every one that is left of all the nations which came against Jerusalem shall even go up from year to year to worship the King,
the LORD of hosts,
and to keep the feast of tabernacles.
Zec:14:17:
And it shall be,
that whoso will not come up of all the families of the earth unto Jerusalem to worship the King,
the LORD of hosts,
even upon them shall be no rain.