The package “eso-pic” can be used to place pictures at specific coordinates on a page. In 2009 that could be done using a command called \AddToShipoutPicture*. The name of that command changed to \AddToShipoutPictureBG* in 2010 {Rosendahl1 [139-140]{G/7/47}}.

Dr Wright began to add the \AddToShipoutPictureBG* command to the BitcoinSN.tex file in the Maths (OLD) project from 18 November 2023 after he began to replace images with pdfs as described at paragraph 481.4 above {See the addition of the eso-pic package at Row 617 of the Maths (OLD)_chunks.xlsx file and addition of the \AddToShipoutPictureBG* command at Rows 6187, 625, 703, 825, 1065, 1067, 1072 and 1074}.

I agree that Dr Wright’s use of that anachronistic command (together with the fact that he was only introducing it on 18 and 19 November 2023) shows that the White Paper LaTeX Files cannot have been the genesis of the Bitcoin White Paper.