Here are some observations, at least indirectly relevant.
Even the mainstream accepts a Giza masterplan at the onset for the entire complex. Since no one has been able to seriously impugn the Sphinx water weathering hypothesis, we believe that whenever the Sphinx was carved, major constructions, not necessarily pyramids, were also built on the sites of present pyramids.
The Khafre pyramid employs two radically different styles of masonry (which ALWAYS means two different periods of construction). The lower courses of the NE corner are made of cyclopean blocks of the order of the core masonry of the Sphinx Valley Temple, with the much less refined and smaller blocks typical of the OK piled on top. Even huger blocks are employed in the surrounding paving blocks. The evidence at Menkaure is less unchallengeable, but it’s there.
The Red Pyramid of Dahshur is built OVER a pre-existing, obviously weathered, megalithic-style chamber (akin to Newgrange), absurdly termed a “plundered tomb chamber” by the quackademic community. What this means is that there was an advanced megalithic aspect to pre-or-proto or even earlier Egypt. This is reinforced by the astronomically oriented megalithic stone circle at Nabta Playa, officially dated to ca. 6000 BC. Throw in 10,000 BC Goebekli Tepe and the recently discovered 8000 BC ultra-refined obsidian bracelet found in Turkey and it becomes clear that the mainstream picture developed by Emery et al, has to be totally rewritten. But that’s all that’s clear. Everything else is up for grabs.