This is a subsidiary post of The New Testament Is a Collection of Collections.
Kostenberger, Andreas J and L. Scott Kellum and Charles L. Quarles. The Cradle, the Cross, and the Crown: An Introduction to the New Testament. B&H Academic, 2009. This quote can be found at Kindle location 850, emphasis added.
There is an amazing conformity of the manuscripts up until the seventh century in matters of content and order. The NT circulated in four smaller volumes: the four-fold Gospel Codex; Acts and General Epistles; the Letters of Paul (including Hebrews); and Revelation. This order can be seen in the earliest manuscripts (i.e., before the fourth- and fifth -century church councils).
Outler, Albert C. “The ‘Logic’ of Canon-making and the Tasks of Canon-criticism” (1980, 14 pages) in Texts and Testaments by March (bibliography). See p. 267-268.