Yup, it's much too early to draw any conclusions. It's estimated that about 360 animals were needed to produce the Codex. The skins are at least from two different species, so we have bovine and ovine skins. There may be more, but not all quires can be assessed because of how far gelatinisation of much of the codex has proceeded (which is different from degradation by ink). Parchment color also differs from animal to animal according to age, color of the coat, etc. It's mentioned that the most degraded pages are near the outer edges of the pieces the codex was found in.DCHindley wrote:The skins from which vellum are made differ widely in quality on account of a number of conditions, such as animal type and age when skinned. I doubt one animal could have sufficed, so we are dealing with numerous animal hides. There is simply going to be variations among them, and we have no guarantee that the vellum sheets were ordered by animal. However, good quality vellum is good quality vellum, and speaks of the manufacturer's skill at skinning and preparing skins to make vellum for writing. Skin side and hair sides may also differ in quality of surface available for writing. This can be seen in Jeremiah, 10:25 - 11:23 library: LUL in both Std & Raking Light, as another hand felt it necessary to retrace some of the letters on this folio because of fading.
There's also the problem that aging of parchment can be very quick if the conditions under which the parchment is kept change. Which means that just transporting different portions of the text to different locations can make a difference. Moves from a dry desert to humid European areas are always very difficult in this regard. I would assume that London is one of the worst places to store objects like this, at least without a controlled environment.
So I guess we will have to wait for how this develops further.