You are a customer loyalty and email marketing expert. Write a detailed, 2100-word guide on birthday and anniversary emails. The guide must cover: 1) Collecting birthdates and anniversary data, 2) Timing and personalization, 3) Offer and incentive strategies, 4) Warm and celebratory copy, 5) Design and visual ideas, 6) Integration with loyalty programs, 7) Examples of effective emails, 8) A/B testing offers, 9) Metrics to track (redemption rate, engagement), 10) Automation setup.