Given the details, several theories emerge:

: Perhaps the date marks the anniversary or birthday of a popular BBC show. The BBC has a plethora of long-running programs, and a special episode or series of episodes could be part of the surprise.

But given the human warmth of BBC birthday surprises, “Sage” is almost certainly a first name.

Viewers took to social media with the hashtag #SageSurprise, calling it "the most wholesome 25 minutes of television in a decade."