There is actually some good reason to think that the date of 135 C.E. that is given the Ryland script is overly early. The Ryland script is a little piece of papar, smaller than a napkin. IT is being dated independantly of any other archelogical evidence that might have accompanied it. It is being dated on the style of writing alone.
Brent Nongbri in his essay "The Use and Abuse of P52: Papyrological Pitfalls in the Dating of the Fourth Gospel" (Harvard Theological Review 98 [2005], page 48). In his conclusion Nongbri states:
quote:
"What emerges from this survey is nothing surprising to papyrologists: paleography is not the most effective method for dating texts, particularly those written in a literary hand. Roberts himself noted this point in his edition of P52. The real problem is the way scholars of the New Testament have used and abused papyrological evidence. I have not radically revised Roberts's work. I have not provided any third-century documentary papyri that are absolute "dead ringers" for the handwriting of P52, and even had I done so, that would not force us to date P52 at some exact point in the third century. Paleographic evidence does not work that way. What I have done is to show that any serious consideration of the window of possible dates for P52 must include dates in the later second and early third centuries. Thus, P52 cannot be used as evidence to silence other debates about the existence (or non-existence) of the Gospel of John in the first half of the second century. Only a papyrus containing an explicit date or one found in a clear archaeological stratigraphic context could do the work scholars want P52 to do. As it stands now, the papyrological evidence should take a second place to other forms of evidence in addressing debates about the dating of the Fourth Gospel."
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