Hi, Dippster. Welcome to DC
I've only made Key lime pie with a Graham cracker crust (is that biscuits for you?), and have never made meringue, so I'm not sure about those; we top it with whipped cream.
You should be able to bake it the day before and do the meringue the day of, though, I think. If the filling has eggs in it, you should refrigerate it until serving.