You are heeding John Darby's FALSE PRE-TRIB RAPTURE DOCTRINE.
And your second statement above is a flat FIB. I am staying with God's Word as written! So saying I'm heeding human taught doctrine is a huge... FIB. So you like Hitler think if you can tell a LIE long enough and to enough people, that they will believe it? Let those in Christ mark your words vs. my coverage from GOD's WORD.
The falling away, or apostasy, that Apostle Paul was revealing about in 2 Thessalonians 2:3-4 is in connection with the revealing of the "man of sin" in Jerusalem playing God, sitting in the "temple of God", a standing Jewish stone temple in Jerusalem for the end of this world!
Now that has NEVER happened yet to this day. So it's obvious that anyone saying it has is a DECEIVER, and is not speaking God's Truth from His Word.
Nope, NOT the falling away that Apostle Paul was talking about in 2 Thessalonians 2. That has NEVER happened to this day. And notice folks, Timothy here has made this same statement TWICE NOW. There's that Hitler type working with the idea of keep repeating a lie enough, in hopes you'll believe it.
The 2nd coming of Jesus Christ IS... ON THE DAY OF THE LORD. Jesus even revealed this when He said, "Behold, I come as a thief..." (Revelation 16:15). In Matthew 24 is where He first revealed that is the 'day' of His future return, by warning that if the goodman of the house had know in what watch the thief would come, he would not have allowed his house to be broken into. (Apostles Paul and Peter revealed that the "day of the Lord" will come "as a thief in the night", using Christ's metaphor about His coming "as a thief").
So far then, Timothy here is batting 1,000 on trying to push LIES against The Word of God.
In 2 Thessalonians 2 verses 1 & 2, Apostle Paul was talking about the 'day' of Christ's future coming AND gathering to Him...
2 Thess 2:1-2
2 Now we beseech you, brethren, by the coming of our Lord Jesus Christ, and by our gathering together unto Him,
2 That ye be not soon shaken in mind, or be troubled, neither by spirit, nor by word, nor by letter as from us, as that the day of Christ is at hand.
KJV
That "day of Christ" phrase is actually the "day of the Lord". And what is the subject just before that? The coming of Lord Jesus AND the gathering of His Church!
So why would Timothy LIE about that, and say Jesus does not come on that "day of the Lord"?
To tell you the truth, I don't think Timothy actually knows... what he is saying, that he has been subjected to another spirit, a spirit that is working against God's written Word.