sasportas, have you ever read 1 Thes. and 2 Thes.? Why did Paul write the 2nd letter to them? He tells us. It was to comfort them. They were troubled and confused about something (Chapter1:7) and he wrote that letter to assure them of things he had ALREADY told them REGARDING THE DAY OF THE LORD. Read Chapter 2 specifically. He says in Chapter2:5 that he had ALREADY told them of these things.
As a prophecy student of the Bible for 50 years, and a former pretrib I might add, yes, I am very familiar with 1 & 2 Thess.
Before I deal with your point, can I ask you a question? What does “the day of the Lord so cometh as a thief in the night,” 1 Thess. 5:2, mean to you? Is it when the rapture happens?
Here is a video from Andy Woods which starting at ten minutes fifteen seconds Pastor Andy gives reasons why The Departure is a better meaning for the 2 Thess 2:3 passage.
Here is a video from Andy Woods which starting at ten minutes fifteen seconds Pastor Andy gives reasons why The Departure is a better meaning for the 2 Thess 2:3 passage: https://www.youtube.com/watch?v=nU-S22S5gTM