Yes, there is.
Select the Stair, go to the Settings Dialog, in the left side tree structure select Monolithic - Flight, and on the right, you will find the Support Endings and Connections panel. You will find 5 light gray circled areas on the image, and you can click any of them and define a Connection type for it. You will probably need to modify the Flight-Landing Connection type and the Landing-Flight Connection type.
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