Interesting reading everyone's responses. I completely agree @frustratedacademic about the amusing commentary on academic life. Though much of it is indeed dated, some things haven't changed, especially the reference to people complaining about their 'crushing teaching loads' of a few hours a week!
I agree also with @Terpsichore that it feels a bit thin, and to me, rather unconvincing in its treatment of the central relationship between Caro and Alan. After his affair with Cressida is revealed, it is barely referred to again! They never seem to discuss it or resolve it - after Caro returns from visiting her mother and going to London it seems to be forgotten.
There were some very enjoyable Pym moments in the novel though, including the sly appearance in Chapter 15 of Pym and her sister in the shape of the two spinster sisters who came to lunch at Caro's mother's. We also get the reappearance of Esther Clovis, of course. And I also loved the names - Grimstone, Horniblow and Stillingfleet!
Overall this wasn't the most satisfying of Pym's novels, but still worth reading, especially for the snapshot of academic life in the early 1970s.