The family moves the house in 'A Moving Experience,' yet the same establishing shots of the outside of the house are shown throughout the series.
Nora is a nurse in the movie and in the Brady 500 2 episodes but by the end of the series she is suddenly going in to business as a caterer with Marcia and Tracy. There is no mention of her quitting her nursing career.
In the initial two episodes dealing with Bobby's car crash, Jan lived away in a different city but for the rest of the series she is apparently close by and working with her dad in the architecture firm. There is no mention of her suddenly relocating.