“Never mind what they’re called! How did they find us? What are we going to do?”
-- Hermione Granger
The trio Disapparate from the infiltrated wedding at the Burrow to Tottenham Court Road. To calm down and figure out their next move the trio duck into an all-night café. However, because Hermione said ‘Voldemort’, enacting the Taboo for the first time, two undercover Death Eaters, Rowle and Dolohov, find their location. A fight ensues, the trio barely coming out on top. Instead of killing the Death Eaters, which would leave a visible trail, Harry tells Hermione to modify their memories.
This duel takes place about a half-hour after Harry, Hermione, and Ron Apparated away from the wedding at the Burrow. Since darkness had set in well before they escaped, and since the sun sets around 9pm in Devon that time of year, we can assume that the battle took place between 11 pm and midnight.