The customer was silently prompted to evaluate the product before it arrived.
Moreover, the evaluation was requested on Sunday morning of a three-day weekend (Friday, Saturday, and Sunday), even though mini letters are not sent on weekends and holidays.
There is no way that the letter would have arrived at that time, so I wish they would at least think a little bit about it.
At the very least, please give us a word or two in advance to let us know that you have received our evaluation.