In a medium bowl, mix the oats and 200ml of water together and let sit for 10 minutes to allow the oats to absorb the water.
In a large bowl whisk together the flours, salt and yeast. In a large measuring cup, measure out the water, add the honey and stir to combine.
Add the oats mixture to the flour mixture and break up the oats with your fingers to distribute equally. Add the honey water and mix the dough until it is completely incorporated and it sticks to your fingers. The dough will be quite wet, slack and sticky.
Cover the bowl with a clean dish towel and let the dough rest for 20 minutes so the flour can absorb the water. After the rest, stretch and fold the dough by grabbing a piece of it from the outside edge then gently lift and fold that piece of dough over to the other side. Continue around the dough in a clock-wise fashion until the dough has tightened a little.
Cover the bowl again and let it sit at room temperature until the surface is dotted with bubbles and the dough has doubled in size (approximately 7-8 hours depending on your room temperature, see note 1). Alternatively, cover the dough tightly, place in the fridge and let rise slowly overnight (see note 2).
Line the long sides of two loaf pans (mine are 9.5" long x 5.5"wide) with parchment so that it hangs over the long sides by about 1". Fold and crease the overhanging parchment with your fingers so that it won't touch the dough as it rises. Grease the short sides of the loaf pans with butter or cooking spray. Set aside.
Lightly dust a work surface with flour. Use a rubber spatula to scrape the dough out of the bowl in one piece. Cut the dough in half and using lightly floured hands gently pat each piece of dough out into a rectangle approximately 12" long and no wider than the width of the loaf pan. Roll up each piece of dough tightly and place each in the prepared loaf pans seam side down. Gently push and flatten the dough into the corners of the loaf pans. Lightly flour the top of each dough and cover both with a clean dish towel. Set aside and allow to rise until the dough rises just above the top of the loaf pans. To test if the dough is ready, press, do not poke, the tip of one floured finger quickly and lightly, about half an inch, slightly off center, into the crown of the dough. If the indentation remains but springs back slightly, the dough is ready for the oven. If the dent fills in, give the dough another 5-10 minutes to rise and re-test.
The second rise will take approximately 2 hours. After about an hour pre-heat the oven to 375 degrees F so the oven is thoroughly hot when the dough is ready. Place the oven rack in the second from the bottom position.
Remove the dish towel and mist the tops of the dough with water or use a pastry brush to apply water evenly to the tops of the dough. Sprinkle oats on top (optional). Bake for 50 minutes or until loaves are dark golden brown.
Remove from the oven and use the parchment paper slings to remove the bread from the hot loaf pans. Place each loaf on its side on a wire cooling rack to cool thoroughly before slicing.