Oatmeal Shortcakes with Spiced Plums

For shortcakes

• 2 cups all purpose flour
• 1/2 cup old-fashioned oats
• 1/2 cup (packed) golden brown sugar
• 1 tablespoon baking powder
• 1/2 teaspoon salt
• 1/2 cup chilled unsalted butter, cut into small pieces
• 2/3 cup whole milk

• 2 teaspoons sugar

For fruit

• 1 pound firm but ripe plums (about 6), halved, pitted, each cut into 4 wedges
• 1/3 cup sugar
• 2 teaspoons fresh lemon juice
• 1/2 teaspoon ground ginger
• 1/8 teaspoon ground cinnamon
• 2 tablespoons unsalted butter

• 3/4 cup chilled whipping cream
• 2 tablespoons powdered sugar