Good day. I am hoping that you could explain why auditors would need to have the audit evidence of a legal letter updated?

Good day. I am hoping that you could explain why auditors would need to have the audit evidence of a legal letter updated? Is it due to timing of the original letter received versus completion of the audit? I understand that a letter from lawyer is to confirm liabilities, which helps confirm completeness of statements and financial statement notes. What I do not understand is why the letter would need updating?

Thanks