Which rhetorical feature best describes “wa-Allāhu aʿlam” inserted into “my friend returned before sunset”?

Supplementary Practice 7: Editing Expressions, Weighing Context and Rhetorical Critique

• Tadhyīl: a closing general maxim
• Partitive substitution of the original subject
• Reversal restriction correcting a wrongly attributed agent
• Iʿtirāḍ: a parenthetic aside within the main assertion