The second Rapture is not guaranteed, but it is a possibility, because should any faithful remain on Earth following the first Rapture, who have come to see and accept Truth and turn their hearts to Yahweh and Christ, there will be a second Rapture prior to Armageddon. But... should no faithful remain following the first Rapture, there will be no second Rapture.
Revelation 14:13 "Then I heard a voice from heaven saying, "Write: Blessed are the dead who die in the Lord from now on." "Yes," says the Spirit, "let them rest from their labors, for their works follow them!"
Those that do not make the grade for the first Rapture, become the blessed ones that see the Truth before the final closing of the door to Salvation; they turn their lives over to Christ, and in doing so, "their works follow them" by being Raptured at Armageddon to the Kingdom of Christ.
"let them rest from their labors," reveals that they are sealed on their foreheads just prior to the door of Salvation being closed and shutting out the rest of wicked mankind. This is just like Yahweh did at the sealing shut of the door on Noah's Ark 7 days before the rains came and rained for 40 days and 40 nights to wipe out that wicked sinful world of people that remained outside the Ark. And so it shall be in these last days when the Holy Angelic Forces slay the remaining people of wicked mankind as Yahweh closes the Chapter on this side of Armageddon in this spiritual war.
Matthew 25:31-36 "When the Son of Man comes in His glory, and all the angels with Him, then He will sit on the throne of His glory. All the nations will be gathered before Him, and He will separate them one from another, just as a shepherd separates the sheep from the goats.He will put the sheep on His right, and the goats on the left. Then the King will say to those on His right, 'Come, you who are blessed by My Father, inherit the kingdom prepared for you from the foundation of the world."
These Scriptures play a dual role. When Christ sits on the throne of his glory in the Promised Kingdom, and the first Century we discussed comes to that Mark in time - the goats will be eliminated. Just like they are going to be from on this side of Armageddon. The Kingdom you inherit, it is actually after the 1000 year Millennium. When Christ submits back to his Father, then you are at Perfection. The Kingdom is complete. The Scriptures repeat future events.
All things that are forecast to happen in this end time, also directly relate to the Kingdom Millennium, and afterwards leading up to the conclusion of the final test, with a few minor variations.
1 Corinthians 15:52 “in a moment, in the twinkling of an eye, at the last trumpet. For the trumpet will sound, and the dead will be raised incorruptible, and we will be changed.”
This refers to the final Rapture; but it also applies to both Raptures, because it describes how you are resurrected from the cousin of sin which is death. It is stated that way because in Yahweh’s eyes, we are all dead unless we repent and seek Christ. When that happens, at the Raptures the sin deserving of the eternal death penalty is shed off of you, and you are raised to an incorruptible eternal life, so long as you do not disobey Yahweh’s Will. Remember this: Sin is corruption. It is also disobedience. If you obey, you will live for eternity.