Gringotts vaults

[Ginny Powell]

No: HPFGUIDX 43934

It occurs to me that there might be a good reason why the "#711" 
reference was removed: to avoid just this sort of speculation on our 
part.

I'm imagining JK writing along, coming to Sirius' note and making up 
a random number for his vault, not realizing it was so close to the 
Stone vault referenced earlier.  Maybe she just likes 7s; lots of 
people do.  When she eventually realized or had pointed out to her 
how close the numbers were, it was removed rather than having another 
number substituted, another number perhaps leading to speculation 
along some other line.

Just IMHO, of course, but it does provide a possible reason for the 
change when no other has been provided.

Ginny, whose name, by the way, IS from Virginia (oh, no, am I evil?!)