Yes. Unlike switching between Essential and Elite (which share similar ingredients and can be swapped without a transition), Legacy is a different type of formula: it's grain-free, red-meat-based, and has a different macronutrient profile. We recommend transitioning gradually over 7–10 days:

• Days 1–3: 25% Legacy / 75% current food
• Days 4–6: 50% Legacy / 50% current food
• Days 7–9: 75% Legacy / 25% current food
• Day 10: 100% Legacy

Monitor stool quality and appetite, and slow the transition if you notice any digestive upset.