I’ve recently moved house. Setting up mail redirection has been a bit of a faff because the postcode database doesn’t quite match reality, so I had to apply in person at a post office. This also required brandishing paper documents, which I don’t have because I mostly bank electronically. Anyway, a week later I go back and and apply. I’m told it’ll start on the 1st November.
I get a letter at the new place, “We’ll start (…) on 4-November, as you requested.”
In reality the extra 3 days is not a big deal; but if you’re going to include copy that calls out the user intent, it had better be real, and not “this is the date arrived at after we lost your form in the post”.