For best texture, allow the cream cheese to come fully to room temperature before mixing the stuffing so it combines smoothly without lumps. The stuffing can be prepared up to 24 hours ahead and refrigerated in an airtight container, then brought slightly toward room temperature before filling the salmon. If your salmon fillets are very thick, lean toward the longer end of the baking time or add a few extra minutes, checking frequently to avoid overcooking. Leftover stuffed salmon keeps well in the refrigerator for up to 2 days and is best reheated gently in a 275°F oven until warmed through to preserve moisture and prevent the seafood from becoming rubbery.