Every 10 days a few blocks wouldn’t match the expected construction rate, and there’s no reasoning why they think it was for the Great Pyramid
Unless there were other crews, like there almost always is in any construction. The journal also specifically names the pyramid, it'd be odd for the stone they're moving to go to the site of the Pyramid of Khufu, mention the name of the pyramid of Khufu, and then not be used for the pyramid of Khufu.