And it came to pass ... - The working out of Nathan’s prophecy (marginal reference) is the clue to the course of the narrative. How long after Absalom’s return these events occurred we are not told.
Related Commentaries of 2 Samuel 15:1
2 Samuel 15:1
1 And it came to pass after this, that Absalom prepared him chariots and horses, and fifty men to run before him.