The three important women in Maxim's life are identified with initials. Rebecca has her monogrammed "R", Beatrice goes by "Bee" (B), and the unnamed protagonist is "I".
Maxim pauses to note that a maid is new. She might be the same as the one who dresses Ich for the ball, or another new maid... Mrs. Danvers, the one responsible for the fiasco at the ball, specifically assigned the maid Clarice to see to Mrs. de Winter. If she's new, she wouldn't have known about Rebecca's costume; if she's malicious, she might be glad to see Ich humiliated.
The heroine just exchanges one domineering figure who belittles her, calls her a child, and tells her she'll never amount to much for two others. (Mrs. Van Hooper to Maxim and Mrs. Danvers). Let us hope that Maxim is capable of character development, and that Beatrice provides a comforting influence in Mrs. de Winter's life...