In bowl, whisk together flour, granulated sugar, baking powder, baking soda and salt. Using box grater, coarsely grate butter into flour mixture; toss lightly to combine.
Whisk eggs with 1/3 cup (75 mL) of the cream. Using fork, stir into flour mixture to form ragged dough.
Turn dough out onto lightly floured surface; pat dough into 1-inch (2.5 cm) thick round. Using floured 2 1/4 inch (5.5 cm) fluted round cutter, cut out biscuits, rerolling scraps to make 10 biscuits. Transfer to parchment paper–lined baking sheet.
Brush tops with remaining cream and sprinkle with coarse sugar. Bake in 400°F (200°C) oven for 15 to 18 minutes or until golden and flaky. Let cool completely; slice in half.
Meanwhile, stir strawberries with 1 tbsp (15 mL) of the sugar; let stand for 20 to 30 minutes.
Whip cream with vanilla and remaining sugar until stiff peaks form. Spread 1 tsp (5 mL) of the jam on bottoms of shortcakes. Top with 1 tbsp (15 mL) whipped cream and strawberries, along with accumulated juices. Top with remaining shortcakes; spoon remaining whipped cream and strawberries over top.