This is the time that the living will be raised from the dead to judgement. Some to eternal life; and some to the lake of fire. There is an order of the resurrections.

Christ has already been resurrected, then the firstfruits will be resurrected, they will return to earth with the Father, then when Christ returns, the saints who belong to Him will be resurrected. Some will be alive at the return of Christ. They will be changed to spirit.

1Co 15:23  But each one in his own order: Christ the firstfruits, afterward those who are Christ’s at His coming.

1Co 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 shall be changed.

Those who are not in God’s church, will be resurrected at the end of the 1000-year reign of Christ.

Rev 20:5  But the rest of the dead did not live again until the thousand years were finished. This is the first resurrection.