Nice numbers; just think,,if you had gotten there a bit later; or the truck that was loaded with the bricks was a bit slower to your doorstep..its very possible you could have received:
AYW 2345432
AYW 2344432
your two brics are only 30,300 and 30,400 notes away...of course in the first brick you would also have had 2345678 ... if you got 1000 notes per brick (as per normal) ... but still I think your number sequences are kinda neat.