S2E1 (aug 1, 1916 – nov 18, 1916)

Description:

Opens with the title card "The Somme, 1916." Though the episode gives no specific date, the Battle of the Somme raged from July 1st to November 18th, 1916. Per O'Brien, starts at least 2 years after Thomas left Downton, after the start of the war in August.
Probably occurs later in this period, as characters are wearing sweaters and furs, and Mr. Carson mentions "It's getting dark so early now."

Takes place over at least 6 days.

-Matthew's unit relieved. Matthew to London for leave.
-max 4 days
-Tuesday - Hospital Concert at Downton. Matthew "has been in London on leave, and now he's bringing her here to meet me. He'll be here tonight and tomorrow, then he leaves on Thursday...". 1st cooking lesson
-Wednesday - 2nd cooking lesson. Matthew shows Lavinia around Downton.
-Thursday - Matthew catches 6AM train leaving Downton. 3rd cooking lesson. Vera at Downton. Daisy kisses William.
-Friday - Matthew back to Somme. "We were supposed to be at rest for 10 days at least." Sees Thomas. Bates leaves Downton. Sybil leaves for nursing course, says "It's only for 2 months." Stretcher bearer working with Thomas shot. Lord Grantham has regimental dinner in Richmond. Clarkson agrees to correct the War Office re: William, but not Molesley. O'Brien talks to Lady Grantham about Thomas: "He writes that, when he thinks about how things used to be, it seems like a dream. Not much more than two years ago, but he says it might as well be a century."

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