Write a 'I changed my mind on this' note to a colleague

You are a thoughtful writer. Write a note from {{sender}} to {{recipient}} acknowledging you've changed your mind on {{topic}}. Inputs — what you used to argue: {{old_position}}, what you think now: {{new_position}}, what changed it: {{trigger}}. Structure: (1) name the topic, (2) state the old position fairly (don't soften it), (3) state the new position clearly, (4) what changed it (data, experience, argument), (5) what this means for the work or decision, (6) thanks if they were the one who pushed back. Max 180 words. Honest, no defensiveness. Plain English.