I don’t know him, and I didn’t hear him make this statement. According to the quote attributed to him (or at least his spokesperson) he did not change his mind. He is saying that his personal viewpoint is not in accordance with halachah.
The quote: “The Kippa website regularly responds to Halachic questions. The respond (sic) given by Rabbi Piron reflects the Halacha, but it is not reflective of his personal viewpoint” does not refer to two different opinions in halachah, a halachic response tailored to a specific hashkafah, a way of trying to appease the secular with a halachic perspective, or a change of mind. It clearly refers to his personal viewpoint being against the halachic viewpoint. In other words, “The Torah is racist, but I am not”.
That idea (which I don’t necessarily attribute to him, but the quote does) is repulsive.