In the morning: feed your starter as you typically would, and allow to rise until doubled and active. Must pass the water-float test (see notes).
Add the raisins to a bowl of hot water (just enough to cover the raisins by half an inch) and soak until ready to add to the dough (at least 20 minutes)
In the afternoon: measure your water into a medium-large mixing boil. Add your sourdough starter (can do float test now if preferred).
Whisk together the bread flour, rye flour, and salt. Add with the honey to the water and starter mixture.
Combine all ingredients together to form a rough dough, you may need to mix by hand to fully incorporate all of the ingredients.
In the mixing bowl, knead the dough for about 10 seconds, then allow the dough to rest for approximately 10 minutes. At this stage it should be quite sticky, and is what is sometimes referred to as the 'shaggy dough'
After 10 minutes, knead the dough in the bowl for another 10 seconds, and allow to rest for another 10 minutes.
After the second rest has passed, drain the water from the raisins and add to the dough, and knead/mix for a final time. You know your dough has a strong gluten structure when it is able to pass the 'window-pane' test. To perform the window-pane test, gently grab the dough from the middle of the ball and gradually begin to thin it as if you were making pizza crust in the air. You want to be able to see the dough stretching until you can see light through the dough without it tearing.
Once you have kneaded the dough a final time, shape it into a rough ball in the mixing bowl, cover with a damp kitchen towel, and allow to rise until evening. It should approximately double in size.
Evening: Prepare the cinnamon filling. Mix the ingredients for the cinnamon filling in a small bowl and set aside.
Place the dough on a lightly floured work surface and stretch gently (avoid tearing) into an approximately 10" by 12" rectangle. Spread the cinnamon filling on the rectangle being very careful to leave a 1½-2" gap along all edges.
Pick up the right side and fold to the middle, pick up the left side and fold to the middle. Pick up the top and fold to the middle, pick up the bottom and fold to the middle. Pull in all of the corners and pinch the seams to form a gentle ball.
Place in your proofing basket and cover with a tea towel. Allow to proof overnight in the refrigerator.