Edith, Rosamund and Cora arrive on the train from London, and greet Mary who is heading into London. Mary should be on the opposite (southbound) platform.
The maid Denker is, in the closed captions, listed as Dencour.
Tom and Sybil are seen playing a game of Pooh Sticks, which was invented by author A. A. Milne and first appeared in "The House at Pooh Corner" (1928). Season 5 is set in 1924, however.