A lot of Bible scholars make a strawman of Paul's teaching on the "Last Trump" sounded in 1Corinthians 15:52 and 1Thessalonians 4:16. They try to link it with John's seven trumpet judgement prophecy of the Book of Revelation. They think we are stupid enough to believe that Paul was teaching on the seven trumpet judgement when we know that historically Paul died about 30 years before John wrote the Revelation, and the Revelation was for John not Paul; So Paul had no idea of the seven trumpet judgement.
Therefore what trumps are Paul talking about? The two in Numbers 10:1-2. The first trump has already sounded to prepare the Kingdom of Heaven here on earth to move out with the first coming of Yeshua, the second can sound at any time -- are you Rapture ready (Luke 21:28, Mark 13: 28-37)?