If I wanted to make this pie in stages and/or a day ahead, would that work? Could I make up until the swamping stage and do that last-minute?

Hi SPark0101 -- you can make the dough and line the pie dish with the bottom half of the dough, and keep it in the fridge. But I wouldn't add the raspberries and bake it until 24 hours before. That still gives you a bit of wiggle room -- hope this is helpful!