Builds the month-end client deck for one Amazon brand — revenue and spend against the previous month and the same month last year, the organic and paid split, category and product mix, what moved and why, and a prioritised plan for next month. Checks that last year's ad data actually exists before drawing a year-on-year comparison. Use when the user asks for a monthly business review, MBR, month-end deck, monthly client report, end of month summary, or the monthly review presentation.
