In a nutshell,
1. The signing of the covenant with antichrist, which may or may not be public, begins the final week, the last seven years of Daniel's prophecy.
2. In the middle of this period, the covenant is publicly broken with the abomination of desolation, and the Great Tribultion begins.
3. Raptures, based on the maturity of the living believers and on the status of dead believers, either as martyrs or overcomers as determined by the Lord, occur at the beginning of the Great Tribulation and at the last trump: "those who are alive and remain." The rapture at the beginning of the Great Tribulation precipitates war in heaven and Satan being cast down out of heaven; the raptures at the end of the Great Tribulation precipate the defeat of antichrist at Armegeddon, and the binding of Satan for a 1000 years.
Other than these facts, I have no sense of the Lord's timing.