Place the shrimp in a large bowl and toss with the baking soda, 3/4 teaspoon salt, and 1 tablespoon seafood seasoning until evenly coated. Allow the mixture to rest at room temperature for 15 to 20 minutes. This alkaline treatment helps the shrimp maintain a tender, plump texture. While waiting, you can prepare the other components.

In a separate bowl, combine the mayonnaise, Dijon mustard, 2.5 ounces fresh lemon juice, Old Bay seasoning, and celery seed. Whisk until the mixture is smooth and fully incorporated. Set this dressing aside until assembly.

Cut the celery into uniform 1/4-inch dice and finely mince the onion. Chop the parsley and measure the dill. Keep all prepped vegetables and herbs ready in separate small bowls for easy assembly.

In a large pot, bring the 8 cups of water and 2 tablespoons lemon juice to a full, rolling boil. Add the shrimp along with any accumulated liquid from the bowl and cook for exactly 90 seconds. Immediately transfer the shrimp to an ice bath using a slotted spoon to stop the cooking process. Let them chill for 2 to 3 minutes, then drain completely and blot dry with paper towels.

Combine the cooled, dried shrimp with the prepared creamy dressing. Gently fold in the diced celery, minced onion, fresh dill, and chopped parsley. Add the smoked paprika, then taste and adjust seasoning with salt and pepper as desired. Use a folding motion rather than vigorous stirring to keep the shrimp pieces whole. Serve immediately or chill for up to a few hours before serving.