Whisk together the first 6 ingredients. Arrange half of the bread cubes in a greased 1-1/2-qt. baking dish. Top with half the blueberries and half the milk mixture. Repeat layers.
Place trivet insert and 1 cup water in a 6-qt. electric pressure cooker. Cover baking dish with foil. Fold an 18×12-in. piece of foil lengthwise into thirds, making a sling. Use the sling to lower the dish onto the trivet.
Lock lid; close pressure-release valve. Adjust to pressure-cook on high for 20 minutes. Let pressure release naturally for 10 minutes; quick-release any remaining pressure. Using foil sling, carefully remove baking dish. Let stand 10 minutes. Serve with syrup.
