Ah! The "missing" cane at last.
My only photo of that cup was taken some years ago while it was in the cabinet. So I could not get an image of the cane at the rear. I never did get around to asking for a viewing of it.
The canes do not seem to be regular Ysart production and I wonder whether they may have come from France when Salvador and family emigrated to Scotland. I don't have any information to back up, or deny, that idea. (But there are also a few "different" style canes used as decoration in some early vases.)