Many of us see "the man of sin be revealed" as occurring at the BEGINNING of those 7 years, rather than at the 2Th2:4 ("sitteth in the temple of God") point in the chronology which is mid-trib (as is Matt24:15,21... Dan12:11,[1-3,6-7]... Rev13:5-7,[1]... Dan7:20-25,27... Rev12:12,14,9... and other "mid-trib" events in the overall chronology of the "7 years");
in the various texts covering this Subject, the correlations connecting the "BEGINNING," the "MIDDLE," and the "END" points are informative in this regard.