Welcome @bphpbc, I also have BPH and am being treated with tamsulosin. I have similar concerns about my long term treatment although I don't have primary biliary cholangitis. I've thought about an alternative to the tamsulosin but haven't made a decision yet. There are a few discussions you might find helpful on alternatives.

--- Benign prostatic hyperplasia (BPH) Surgery Options: https://connect.mayoclinic.org/discussion/bph-surgery-optons/
--- Benign prostatic hyperplasia (BPH) Treatment Options Experiences: https://connect.mayoclinic.org/discussion/benign-prostatic-hyperplasia-bph-treatment-options-experiences/

Have you thought about or looked into alternative treatments (minimal invasive, non-medication) like Uro-Lift?