From the BN=Press Formatting Guide:
"Chapter 'Sink' – The chapter text starts down in the middle or lower third of the page. This is usually done if the chapter starts on a right hand (or odd) page. A good way to create a Chapter Sink is to define a Chapter Title paragraph style that specifies the amount of spacing you want to appear before the title and use that consistently throughout your book. Use this approach rather than pressing return multiple times to create the sink."

The only method I found in the Style settings that might work was in Paragraph settings, Spacing, Before. Unfortunately this doesn't yield the desired results. I am applying the "Page Break before" succesfully.
Surely I'm missing something and I can do this modifying my Heading 1 style.