Dating the winchester cannon
However, it is not explained why, that if Sam is Lucifer's true and destined vessel, he would have to drink demon blood, whereas Dean, being Michael's true vessel needs no preparation.
The first five seasons of the show take place in the current time.
In the teaser for 1.01 Pilot, John, Sam and Dean are clearly seen huddled together on the hood of the Impala as their house burns.
In the Origins comics, Peter Johnson had John acquiring the Impala after Mary's death.
You can see the different versions of the journal there.
Paley Television Festival that they made a mistake in the script -- initially Sam was meant to be 20, then they aged him up to 22, but neglected to change Dean's line from "two years" to "four years." Therefore, it may have been the creators' intention that Sam has been at college for four years.There is also the possibility that Sam's first two years in college were as a high school student participating in a dual-enrollment program.This would mean that Sam earned college credits in his final two years of high school and was, in fact, a senior in college by the time of the pilot.This is confirmed by a calendar seen on the wall in 5.21 Two Minutes to Midnight.
Then, as stated in 6.01 Exile on Main St., a time jump of "about a year" occurs between season five and season six.
That would mean that the date halfway through season six should be sometime around November 2011.