Nobody will be left behind. The tribulation will have already happened when the Second Coming occurs. 2 Thess. 2:8 And then the lawless one will be revealed, whom the Lord will consume with the breath of His mouth and destroy with the brightness of His coming.
You are either raptured or killed by the brightness of His coming. So no stragglers. A thousand years in Heaven to get acclimated and then the wicked are brought back for a judgment.
The Rapture is Not the 2nd Coming. The Rapture does not involve Christ returning, only the Church being called out of the world, thereby removing the restraining hand of the Holy Spirit, allowing the beast his free reign. THEN, Christ returns.
And there is no 70th week either right?
Or Temple?
Or AntiChrist?