Steve, I have heard several people talking about 10.5 years after the first Rapture, with another rapture 7 years later, and then the great tribulation.  I have thought, and read, a lot on this, and I do not see where a 7 year tribulation can evolve into a 10.5 year time sequence.  We are clearly told that There is the Rapture, then there is 3.5 years (and some thing there will be a second, partial rapture then), followed by the setting up of the Abomination in the Holy of Holies and the Battle of Armageddon which will last another 3.5 years.
 

Your explanation would be appreciated!

Marie Achgill