Pour the milk over the sugar & yeast in a large bowl. Let it sit for ten minutes, do not stir. Bubbles should form.
In another bowl, combine the bread flour, pie spice, and salt.
After yeast has been activated, add the eggs, melted butter, and pumpkin.
Begin adding the flour in 1 cup increments until it is firm enough to roll by hand. Pour onto a lightly floured counter and knead, working in remaining flour, until gluten is fully developed. About 15 minutes. Or you may use a mixer with dough hooks attached.
Place dough into an oiled bowl, oil the top and cover with plastic wrap. Place in fridge overnight or at least 8 hours.
In the morning, after dough has at least doubled, roll out to about 1/4" thickness on a lightly floured surface. If the dough is too elastic, cover and let rest ten minutes before you resume rolling. The ideal dimensions are 16x21.
Combine the sugar and cinnamon in a small bowl, then spread butter over the rolled dough, leaving 1" clean on the side farthest from you.
Sprinkle cinnamon-sugar mix over dough and press in the filling and pecans (if using) then roll, sealing the clean 1" by wetting it slightly with water. Cut into 12 pieces with a sharp knife or dental floss, and set each individual piece onto a lightly greased sheet pan. Be sure there is at least an inch between each roll or the rise will be affected.
Let sit, covered, in a warm place until doubled in size, about 30 minutes.
Preheat oven to 400F
Bake rolls until golden brown, about 15-17 minutes. While rolls are baking, prepare the cream cheese frosting;
Beat together cream cheese and butter until well combined. Sift in confectioners' sugar, bit by bit. Beat about 5 minutes until light and fluffy, then briefly beat in vanilla. Spread frosting on warm rolls before serving.