v4.4.2

Fixed

• A number format the file declares itself is no longer mistaken for the builtin format its
  index stands for. The format numbers 14-22, 27-36, 45-47, 50-58 and 71-81 are reserved for
  builtin date formats, several of them localized, so a cell using one carries no format code
  of its own. But a file may register a code for such a number - XLS writers do it routinely,
  1C among them, and a workbook converted from XLS keeps doing it in XLSX - and it has then
  redefined that number. The reader typed such cells by the number alone, so an article number
  like 043, stored as 43 under the custom pattern 000, came back as a timestamp of
  1900-02-12 with no error raised. The declared pattern now decides, for the cell value as well
  as for format-category of the cell style; a number used without a declaration still means
  the builtin format it always did.