Thank you for both your input, which I value, and your kind words. I have followed your posts for quite a while and always find them informative and humanitarian, which I enjoy. (And yes, blocking trolls is sometimes needed. I am often asked: am I Jewish? - and this question is never meant well. In G+, a poster should mean well, or be reported/blocked.)
I followed the news for Sana'a manuscript as closely as I could, from the time of its discovery. Somehow I lost track for a time, so am delighted to learn how the analysis has got somewhere useful.
It seems the C14 dating is regarded as definitive; maybe, though it has a habit of confirming the view of the person paying for it. A chronology:
> Muhammad spent his last ten years, from 622 to 632, as the leader of Medina in a state of war with pagan Mecca.http://en.wikipedia.org/wiki/Military_career_of_Muhammad
> The Byzantine-Arab wars begin in 634.
> The conquest of Syria, 637
> The conquest of Armenia, 639
> The conquest of Egypt, 639
> The manuscript: 75% probability from before 646
The suggestion that Islam came after the conquest of Jerusalem is still a possibility, through the window of opportunity is small.
At least the manuscript takes us further back and that is a useful achievement.
Hijazi script, also Hejazi; Arabic: خط حجازي ḫaṭṭ ḥiǧāzī, literally "Hejazi writing", is the collective name for a number of early Arabic scripts that developed in the Hejaz region of the Arabian peninsula, which includes the cities of Mecca and Medina. As the name suggests, it is associated with the Hejaz region of Arabia. This type of script was already in use at the time of the emergence of Islam. It was one of the earliest scripts, along with Mashq and Kufic.http://en.wikipedia.org/wiki/Hijazi_script
I am not sure that script = language. After the discovery, there was a claim the language is Syriac. I don't know if this question is answered.
The lower text of the Sana'a palimpsest frequently differs from the standard text of the Qur'an, although only "a small fraction of the variants do make a difference in meaning." [Sadeghi & Goudarzi 2012, p. 19.]http://en.wikipedia.org/wiki/Sana%27a_manuscript#VariantsThe Sana'a Qur’an shows only a few fragments and has many important differences compared with the modern Qur’an.http://goo.gl/kaJegU