The onus is on you! You're the one claiming they are immortal! If they were resurrected immortal (1) they would still be alive on earth today
It isn't necessary for those bodily-resurrected individuals to be located on this earth in order to be alive in those immortal bodies. The destined inheritance that all believers are to experience is to be presented faultless before the presence of God's glory with exceeding joy (Jude 24). It isn't enough for a believer who has died just to get above ground in a glorified body made immortal. The very purpose for changing those mortal remains into a glorified body form is to fit it for a heavenly abode with our Creator.
Paul would not have written that faithful saints shall be changed from mortal to immortal and corruptible to incorruptible when the last trumpet sounds. That won't happen before an hour that is coming.
Paul himself told Felix in Acts 24:15 that "there is
ABOUT TO BE a resurrection of the dead, both the just and the unjust". Paul also told Timothy in 2 Timothy 4:1, "I charge thee therefore before God, and the Lord Jesus Christ, who is
ABOUT TO JUDGE the quick and the dead at his appearing and his kingdom..." James 5:8-9 also wrote concerning Christ's return , "Be ye also patient; stablish your hearts: for
the coming of the Lord has drawn near...the judge standeth before the door." These were all warnings of
Christ's imminent return in that first century, in which the bodies of the dead believers would be changed to the immortal at the last, seventh trumpet that Revelation wrote about.
You and I are not waiting for that last, seventh trumpet, which was already blown back in AD 70; we are waiting for the feast of trumpets in the seventh month of a year in our future, at the last, 3rd resurrection harvest. The rituals under Mosaic law provides the symbolic pattern for these three separate "harvests" of the saints' bodies out of the grave.
It never mentions Him coming a third time. That is complete nonsense. The following also only shows Him coming back once and it will be in the same manner as He ascended to heaven:
Of course Christ would bodily come in the same manner in which He left at His ascension. That's a given. But scripture speaks of
the continued flow of human history AFTER Christ's second coming return. Zechariah 14:16 wrote about
the "year to year" passage of time AFTER Christ's second coming to the Mount of Olives in Zech. 14:4-5. Also, Matthew 24:21-31 said that the "Great Tribulation"
(which was followed by Christ's return "immediately AFTER those days"), would never be duplicated at any time in history following that period of disasters. That means regular periods of tribulation would still be occurring over the span of human history on this planet
after Christ's return, but with none that would ever duplicate the former "Great Tribulation" in the distant past.
With ordinary human history continuing AFTER Christ's second coming, people are still being born and dying, all of whom must also stand before the judgment seat of Christ to receive the things done in their body, as required in 2 Cor. 5:10.
This requires a third coming and a third resurrection event to wrap up human history at the final culmination point.
Christ also spoke a parable in Luke 12:38 comparing His coming to a returning lord who would come "in
the second watch AND the third watch". If that lord found his servants faithfully watching for
His return on BOTH occasions, all of those servants would be blessed.
Christ predicted He would return before some of those He was speaking to in Matt. 16:27-28 had yet tasted of death. That required a first-century return in that generation - the "
second watch" return, if you will. You and I are now waiting patiently for Christ's return
"in the THIRD watch". If we are faithful in our service to our Lord, we will be blessed servants indeed, as Christ promised.
