What you call "variants" is in fact "differences" and what is "different" is not the same. Therefore yes, the Sanaa palimpsest is NOT (rasm, sura order, verses adding/lacking, etc)
I actually wonder about carbon dating accuracy of those Sanaa Quran manuscripts
from that wall of Yemen Mosque .. If I remember correctly (some where it is published ) Sanaa Quran manuscripts carbon dated as the year 692 with some 90% accuracy... (NOT SURE ABOUT THEIR ERROR BARS)..
So the question now is, if we eliminate Muhammad(prophet of Islam) and those four rightly guided caliphs .. THE RASCALS OF ISLAM.. THE ALLEGED TWO FATHER IN-LAWS & TWO SON IN-LAWS of alleged prophet and all these TEN QURAN ENCHILADAS OF ISLAM ((the chain of narrators of Quran)) from the history of Islam ..
Umar ibn al Khattab ., Uthman bin Affan ., Ali ibn abi Talib ., Abu Musa al Ash'ari ., Ubay Ibn Ka'b., Abdullah ibn Masood., Zayd Ibn Thabit., Abu Hurairah., Abdullah Ibn Abbas., Abu al-Darda
if we remove all those guys as silly stories of Islam from hadith., then the questions to answer are
1) . who were the authors of those Sana Quran codex in the year 692?
2). why were they found that far in Yemen if we assume, Islam and Quran appears to be originated some where in Syria/Jordan/Israel/Eastern Arabia/Iraq...??
the codex we have today, it is ANOTHER codex. So there were different codexes.
Well I am not sure that the present Quran should be considered as Quran codex.. IT IS A BOOK OF MANY QURAN CODICES
AND CONFUSION ., On top of that. rascals added and removed verses here and there and and juggled those surahs around and filled the book with irrelevant alleged revelation order ..