Deferring To The Arukh HaShulkan
He cites his grandfather R. Yosef Eliyahu Henkin as considering the Aruch HaShulchan as more definitive than the Mishnah Berurah.
- It is a more recent authority relative to the Mishnah Brurah. Although Aruch haShulchan on Choshen Mishpat preceded the Mishnah Berurah, the part on Orach Chayim was published up to 10 years after Mishnah Berurah).
- He covers all of the Shulkhan Arukh
- More importantly, the Arukh HaShulchan reflects the minhagim of the time, while the Mishna Berurah is much more precedent/text-based.
Read more about this topic: Yehuda Henkin