"الناسخ والمنسوخ في الكتاب والسنة" by Abu-Ubaid Al-Qasem Ibn Salam (أبو عبيد القاسم بن سلام ), died 224 H. (not to be confused with Abu-Alqasem Hebatullah Ibn Salama, died 410 H.), published in 2006 by Dar Al-Kotob Al-Ilmeya in Beiurt, Lebanon. The book was edited/verified by Mostafa Abd-Alqader Atta (216 pages).
This book has remarkably detailed information about old scholars and references, which the editor added to the original manuscript through the introduction and through numerous
footnotes. The editor certainly added value to the original manuscript by Abu-Ubaid, which is a typical pro-abrogation book of the old school.
Abu-Ubaid died in 224 A.H., much earlier than many who are 'credited' with establishing the abrogation doctrine, e.g., Al-Jassas who died in 370 A.H. and Al-Tabari who died 310 A.H. The book has all the ingredients of the abrogation doctrine as discussed in old books that were written afterwards, so I see the merit of the editor's calling the book the earliest in classifying the abrogating and abrogated.