I checked the first video and out the gate at 2:59 it makes a claim that, "The ' One Day as a Thousand Years' Prophetic Principal" which, "This principal teaches that a literal day can prophetically represent a 1,000-year period." Is backed by (2 Peter 3:6)

Here is 2 Peter 3:6

2 Pe 3:6 KJV “Whereby the world that then was, being overflowed with water, perished:”

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This has nothing to do with the postulate which the authors are building a whole series on.