Preheat oven to 425 Degrees.
1. Bake squash cubes in a large roasting pan with 1-cup water until soft, about 40-45 minutes.
2. When cool enough to handle, place squash in a medium bowl; season with salt and mash with a fork.
3. Meanwhile, slice apples into 1/8-inch thick wedges and place in a medium bowl. Add lemon juice and toss to combine.
4. In a medium skillet, melt 3 tablespoons butter over medium-high heat. Add 2 tablespoons brown sugar and cook, stirring, until sugar dissolves. Cook apple slices in the butter and sugar in 3-4 batches until golden and caramelized, about 1 minute on each side. As they finish cooking, transfer to a plate and set aside.
5. In a medium skillet, melt 3 tablespoons butter over high heat. Add 2 tablespoons brown sugar and cook until sugar dissolves. Stir in 4 tablespoons cream and the Calvados and cook until slightly thickened, about 1 minute. Remove from heat and add to squash, add in honey, whisking well to combine.
6. Transfer squash mixture to a buttered 3-quart ovenproof casserole. Arrange apple slices over squash and set aside.
7. In a medium skillet, melt remaining 3 tablespoons butter over medium heat. Add remaining 2 tablespoons brown sugar and cook until dissolved. Add remaining 2 tablespoons of cream and cook, stirring, about 30 seconds. Stir in the orange juice and cook for 1-2 minutes, until thickened and dark brown. Pour over the apples and cover with aluminum foil.
8. Bake until heated through, about 30 minutes. Remove from oven and serve immediately or let stand at room temperature for up to 30 minutes. Sprinkle with cinnamon before serving.