Getting letters from the Canadian High Commission

[gonatgo]

My lawyer just informed me this week that she received a letter from the Canadian High Commission in London. The letter is dated August 21, but she is claiming that she just got it this week. Pretty unbelievable to me. So my question is, does the High Commission send letter by regular mail? Aside from asking my lawyer to show me the envelope it was mailed in (as it would have the date it was posted), is there any way I can find out how this very important letter seemed to get 'lost' in the mail until now?

Thanks!