We had an issue where the whole IPv6 block /32 was blackholed due to fat-fingers syndrome. The mask for the prefix was accidentally missed and IPv6 traffic just went off.

Almost everything was fine for a long time because there were some more specific routes advertised from other locations with /48. But because one of our ISPs (multi-homed) didn’t announce one of missing /48, thus it was routed (actually blackholed) via the unexpected node.

We cannot fix all the problems people do (fat-fingers), but a trivial fix to make sure others do not step on the same mine is nice to have.