>>>First, the sentences you refer to here are addressed to Rick Strahl, not to Alan Griver.
>>
>>This was in your original post, addressed to All, but concerning YAG's response to your private e-mail:
>>
>>The reply, with hopefully the reasons I ask for, is required now, rather than next month.
>
>Yes, you're right. That one is in the main message.
>
>Now, could you, as a native speaker, and/or as an American, tell me: What is impolite about it.

PMFJI, Peter.

Maybe it is because you haven't FULL command of English. That sentence is phrased with a demand - the opposite of a "polite request". It sounds more like a final demand for late payment of an overdew bill. A polite phrasing would have been:

"A reply, hopefully with the reasons I ask for [sic], would be greatly appreciated as soon as possible"

or:

"An early reply, hopefully with the reasons I ask for [sic], would be much appreciated"

If the "next month" bit is essential:

"Unfortunately a much later date will be of little use to me"

If I were to receive a"demand" from you like that then my reaction would be that you can go and get knotted.

My two penn'orth