Kathleen, now that I think about it I may be entirely mistaken about the house.

The second sentence in chapter 25 reads, "Since the death of her husband, who had traded with success in a less elegant part of the town, she had resided every winter in a house in one of the streets new Portman Square". I had assumed that they lived in that less elegant part of town and Mrs. Jennings still had friends from there, but I may be wrong - perhaps Mr. Jennings only worked there.