The night bus service only runs the nights "before" Saturday and Sunday[1]. It's a small university city with 300k population (600k greater metropolitan area).
For that, you can use "spike filing". Place everything incoming you might need on top of a spike (or on top of a pile or in the front of a folder). The automatically sorts by traverse chronological order, making it easy to both retrieve old documents and to know the age so you can discard older ones.
The "AAA" is a typo, they probably mean "AA777" for American Airlines 777[1].
A far as why the number 777 is amusing, it's gambling. The combination 777 is a jackpot on a slot machine, Additionally AA777 is a great hand (full house) in poker.
[1] https://www.verbundlinie.at/en/customer-service/arriving-in-...