I don't think this governess had been mentioned earlier in the story. I wonder if JA had some particular reason for introducing her here? She seems unnecessary to me, as Mrs Smith has heard news of the Elliots and Anne's arrival in Bath through Nurse Rooke. Wouldn't it have been simpler just to have Mrs Smith send a note to Anne asking her to visit? For that matter, how does Anne know the old governess is in Bath, but not her old friend Mrs Smith? Was the governess mentioned just to give us, as an additional proof of Anne's goodness (as if we needed one!), that she visits her old governess? Or is this just one of those little flaws JA would have fixed had she had more time to revise...?