Preheat oven to 250°F. Line a large baking sheet with parchment paper.
Place bread cubes on tray, drizzle with 1/3 oil. Toss to combine. Salt and pepper lightly.
Bake 8-12 minutes until lightly toasted. Remove bread from tray, place in a large bowl and set aside.
Increase oven temperature to 425°F. Place squash on same baking tray. Drizzle with remaining oil.
Mix spices together in a small bowl. Sprinkle over squash, toss to coat completely.
Roast 20-25 minutes until tender. Set aside to cool slightly. Once cool add to bowl with bread cubes along with cranberries and seeds. Drizzle with desired amount of vinaigrette. Toss to combine.
Arrange arugula on a large serving platter. Spoon salad over greens. Garnish with fresh lemon wedges and server warm.