@Cow A normalized version,
{{'18882021579', '8882021579'}}
, of that pattern is already on the number blacklist. You can use
!!/bisect-number 18882021579
to determine which entries on the number lists match that pattern, which would tell you: Matched by
18882021579
on
line 3484 of blacklisted_numbers.txt: 18882021579 found verbatim