Strange double post on spiral stair railing

[David Collins]

Can someone who has a better relationship with the stair and railing tools tell me why I’m getting a double post at the top of this associated railing for a spiral stair? Both the stair and the associated railing baselines are simple arcs with nodes only at the endpoints.
I’m guessing it has something to do with the stair settings because I can create a simple railing on the floor following the same arc with posts only at the two endpoints. If I turn off the railing association, I can delete the extra post, but I’d like to keep the two elements linked if I can.

[Barry Kelly · Accepted solution]

The stair has an option to end with a tread or end with a riser.
This does affect how an associated railing finishes at the end, especially if the railing does not carry onto the landing.

Barry.

[David Collins]

Thanks Barry, that fixed it. The logic escapes me, but I suppose it makes more sense with a standard stair and landing.