Like Doc had done with his letter in 1885, Clara sent hers via several generations of Western Union, with instructions that it be delivered to Marty at "the highest attainable level of education prior to university, on the first Monday of March, 1986". When the Western Union man delivered the letter to Marty during a history class at Hill Valley High School on the aforementioned date, the letter deliverer mentioned to the teacher that his supervisor at Western Union experienced a case like this when he was young.