I'm not able to find a source that includes the page numbers online. Do you have the book on hand? If so can you confirm that the page count includes all end material (acknowledgments, afterwords, notes etc.)
I have the book in hand. The final numbered page of the text is p376. There is a unnumbered advert on the facing page ("Welcome to the world of Georgette Heyer. We hope you have enjoyed Friday's Child ... explore further novels in this collection" and the reverse is blank.
https://www.goodreads.com/book/show/5...
ISBN 9781787466432