I'm looking for books/papers on the decline of the aristocracy in Britain during this time but I'm not sure where to find any. I really want to read something that focus more on the role of the serving class, ideally during this time bc of the changes occurring during this time but even content that focuses more on the history of the serving class in Britain would be neat :0 also want to know more about the history/role of the valet in particular but that might be too specific
Since you say you'd really like something that focuses on the serving class, I have a few recommendations:
Life Below Stairs: True Lives of Edwardian Servants, by Alison Maloney - This book is largely based on oral histories documenting the experiences of individuals in service in the 1900s, although there is other contextualizing information given - there are no citations, but there is a short bibliography at the back of the book. It's not scholarly, but it's a good way to get selections from the oral histories without tracking down all the oral histories!
Up and Down Stairs: The History of the Country House Servant, by Jeremy Musson - More academic, this book does have citations! It's also about a rather broader range of dates, with the main focus from the 18th century to the 1920s-30s, and it has quite a lot of detail about relations between employers and servants and how they changed over time.