Bren, Dolly, Tony, Anita, Phillippa, Stan and Twinkle are the only cast members to appear in every episode of the series.
Spoiler: The baby on the fire escape is found, at the very end of the episode, to be Anita's. For those who pay close attention, they could have worked this out earlier - when there's a close-up of the baby after it's found, it is wearing the knitted hat Anita was showing her work-mates in the episode 'Catering'.
The baby on the doorstep is Anita's.
Goof: Petula and Phillipa introduce themselves to each other whilst Bren and Phillipa are discussing their holidays. However in the first season, Phillipa and Petula had several interactions in episodes 1x03, 1x04 and 1x05.
During the argument between Dolly and Phillipa, Phillipa calls Dolly 'homophobic'. In the next episode, we discover Dolly has a gay son, who is again mentioned in 'Minnellium'.
Philipa forgets to tell the staff not to come into work so its her fault how the ladder got jammed in the kitchen.
Jean misreads the advertised job as 'light housekeeping' which is exactly what Graeme does in the Goodies' episode 'Lighthousekeeping Loonies'.
When Jean first meets Nicola, she asks her for a croissant. Jean's response is "You can have belly-dancing classes if you like, but we do need to know". In the following episode 'Catering', Betty is seen in the canteen on her way to a belly-dancing class.
The replacement walks out to go to an interview in Scotland for a lighthouse keeper.
In this episode we finally discover the name of the company in which the show is set: HWD Components.
This is the first of a few times that Stan wears a wig.