Hi, John -

My "loosely-held speculation" listed 10 items.  The seventh was "The Dragon is given authority over every tribe, tongue and nation (Rev. 13:7) for 42 months" - what was in view was the EVENT of this grant of global authority. 

The 42 months and the 3½ years in Item #8 are the same period of time. 

I am NOT suggesting that there are 42 months of misery under The Dragon followed by 3½ years of God's wrath (often simply called "tribulation" or "great tribulation").  The 42 months is the same period of time as the 3½ years (and incidentally the 1,260 days of Rev. 12:6) and this period ends with the battle of Armageddon at about the midpoint of Daniel's 70th week.

Sorry for any confusion.

Best,

Steve