Preheat the oven to 350°F (177°C). Prepare a 9 × 13-inch baking dish and note the pan material used for testing.
Stir together 1 tablespoon mayonnaise and 1 teaspoon Dijon mustard in a small bowl.
Keep the 12 Hawaiian rolls connected and cut the slab horizontally. Place the bottom slab in the baking dish. Spread with the mayonnaise-Dijon mixture; top with 3 oz of the Swiss cheese.
Spread 14 oz of safely cooked turkey evenly over the bottom cheese layer. Distribute 1/3 cup of thick whole-berry cranberry sauce across the turkey without pooling. Cover with the remaining 3 oz Swiss cheese and replace the top roll slab.
Mix 2 tablespoons melted unsalted butter, the remaining 1 teaspoon Dijon mustard, 1/2 teaspoon dried thyme, and 1/4 teaspoon garlic powder. Brush evenly over the tops without pouring extra liquid into the dish.
Loosely cover with foil. For the initial V1.0 trial only, start with approximately 12 minutes covered, then check during an initial 6–10 minutes uncovered. These are NOT validated times. Continue baking as needed until reheated turkey reaches 165°F (74°C) throughout, checking the center and several edge locations with a food thermometer. Tent with foil if tops brown too quickly.
Once every checked turkey portion reaches 165°F, remove from the oven. Rest briefly and cut between the rolls to yield 12 individual sliders.