Who are the survivors that will go into the earthly kingdom?
The survivors entering the earthly kingdom are flesh-and-blood believers who endure the tribulation and the battle of Armageddon. They are from all nations and must be born again, for no unbeliever can enter that kingdom. They will come up from year to year to Jerusalem.
Les explains that these survivors are distinct from the Church. The Church will be translated before these events and return in resurrected bodies, not flesh and blood as we know it, not procreating or marrying. But there will be people in the earthly kingdom who are flesh and blood. They are those who have survived the awful events of the tribulation and the battle of Armageddon, and they are believers. No unbeliever will go into that kingdom, flesh and blood or otherwise. Les connects this to John 3, where Jesus told Nicodemus that except a man be born again, he cannot enter the kingdom of heaven, identifying it as the same kingdom—the kingdom of the King coming upon the earth. The surviving people of all these nations will come up from year to year to the city of Jerusalem.