Scott,
You are 'mostly' correct.
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Exception:
3. Handrails may be interrupted within the width of a tread where the wall configuration changes.
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It could stop in the corner and the start back up to go the other direction. The corner is the wall configuration change
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"It could stop in the corner ", nope, because it says "Handrails may be interrupted within the width of a tread ", and that corner is 'at the corner of the tread'.
The lower handrail would need to, at a point directly above that top riser in the lower flight of stairs, turn horizontal along with the winder, jog up vertically at the corner, turn back horizontal along with the next winder, then, at a point above the lower riser in the upper flight of stairs, the handrail would need to meet with the upper handrail.
Or, they could make the handrail continually sloping from a point above the top riser in the lower flight to a point above the bottom riser in the upper flight, but ... that would take a lot of work and still keep the handrail within its allowable height range (if that is even possible).