I have the dubious honor of being SSSS’d on the majority of my return trips to the USA (currently awaiting redress inquiry). My experience at LAX recently is that if you try another BP, after being SSSS’d, the new BP WILL NOT scan and will return an error (I goofed and lost track of my connecting BP so had to reprint). But AA systems / kiosks / etc. will still print a new BP with no indication to the passenger that the BP is not valid. CLEAR reps and TSA were not sure why and had no idea it was due to SSSS. Thankfully I finally found my original BP crumpled up at the bottom of my carryon.