The up or down orientation is used in combination with the constraints to determine the desired layout to the next level. You may want to design a stair working from level 1 down to basement and then another from level 1 to level 2 which has a different vertical distance.
AutoCAD Architecture 2021 Help | To Create a U-Shaped Stair With User-Specified Settings | Autodesk
https://help.autodesk.com/view/ARCHDESK/2021/ENU/?guid=GUID-B2F17280-E5D5-43BC-99B2-F9804544FFEF
It sounds like you are drawing two separate stairs for the same function rather than displaying the same stair in separate plans. Are your plans in different cad files or something different. Here are a couple of examples:
- same file same tab separate paperspace viewports
- same file separate tabs
- same file, all in model space
- same file one tab, one viewport (kind of the same as 3 really)
- some combination of the above with plan xref’d into drawing.
- copies of the stairs in the same plan using different display settings for each.
- multiple cad files with plan xref’d and different display settings based on plan elevation.
- project based constructs into separate cad files.
There are probably more ways than I can think of but based on the idea of one stair drawn up and one stair drawn down for a mezzanine plan, you could draw two separate stairs and display them differently.