This long and informative article includes information I have not seen before. On that basis, I need to revise my previous conclusions about the manuscript.
When Steve Green, the president of Hobby Lobby, presented the book in 2013 at a Religion Newswriters Association conference, the founder of the museum and its board chair said that the manuscript dated to the ninth century.(Original emphasis.) This paragraph establishes that the manuscript was first presented in 2013. That must mean that it is the "Hebrew siddur" noted at the time here. The discovery of its actual Afghani provenance in 2017 led to a new C-14 dating which established it eighth-century date.
As for its layout, the book currently on display seems to combine two originally independent quires, with more writing added after they were combined. Herschel Hepler, "associate curator of Hebrew manuscripts at the Museum of the Bible":
“I think there were two quires that had independent lives from this manuscript in the eighth century. One the Haggadah. One the beginning of a poem” about Sukkot, Hepler said. “Someone came into possession of these two different quires of four sheets of parchment and wanted to combine them, and I think this is the person who wrote the Sabbath morning prayers.”Thus the codex appears to have inconsistent layouts. One widely posted photo of it (see links here) has 14-15 lines. The available photos I have seen of the 2013 book (e.g., here) have 11 lines. But a more recent photo of the current book also has 11 lines. And a photo in the Israel Today article shows 12 lines, one blank.
I conclude therefore that there is only one book, first presented in 2013 and now on display in the MOTB with new information. Please pardon the confusion.
Background here and links.
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