Here is a illustration of the issue. The three stairs have the same setting and the plan view is from the ground floor. I expect the one in the middle and the one the right to be drawn without a break mark as they both are below the FPCP of the ground floor. But this is only the case for the middle, the right (which is placed completely outside the range of the lowest level) is drawn with a break mark. The break mark seem to be placed as if the stair was placed with zero offset from ground floor.
My guess is that since the stair to the right does not physically intersect any stories it doesn't have any Relevant Story which in turn breaks something in the calculation of the break mark position.
