It turns out that 2 Thessalonians chapter 2 is not about the apostasy of the Church or the removal of the Holy Spirit from the earth during the Tribulation period. It is about looking to the Old Testament prophets in order to recognize end time events!

2Th 2:3 Let no man deceive you by any means: for that day shall not come, except there come a falling away first, and that man of sin be revealed, the son of perdition.

Paul is not revealing new prophetic information here. He is reminding us about the prophecies of Isaiah (Isa 14:12) and Daniel (Dan 9:27). In verse 3 above, "a falling away" is the falling of Satan from heaven as explained by Isaiah. The "man of sin" will defile the temple as explained by Daniel.