My Form 5472 penalty notice went to an old registered-agent address. How should I frame the response?

I only learned about the penalty because my former registered agent finally forwarded a notice packet months after the IRS had mailed it. The LLC had already changed mailing arrangements, but the old address was still sitting in part of the administrative file, so I now have a late-discovered Form 5472 penalty issue that is partly about the notice path and partly about the underlying filing problem.

I do not want to overplay the address issue if the IRS really wants the corrected filing first. At the same time, the notice timing matters because I genuinely did not have the same opportunity to respond quickly that I would have had if the mail had come to the current file. I want to understand how to present both facts without making the response feel scattered.