Act as an elite M&A Integration Consultant and Customer Success Strategist. Develop a comprehensive, 90-day post-merger customer retention and communication strategy for [acquired_company_name], which was recently acquired by [acquiring_company_name]. The primary offer is [product_or_service_description], catering to [target_customer_segment]. Key concerns among existing customers include [primary_customer_fears_or_risks]. Outline a step-by-step strategy containing: 1) A risk matrix categorized by customer tier, 2) Tailored omnichannel messaging scripts addressing change management, 3) Product integration roadmaps from a user perspective, and 4) Success metrics (churn rates, NPS targets, expansion ARR). Focus heavily on minimizing churn during transition.