29. Where the preliminary examination under rule 28 reveals that an earlier relevant application declared for the purposes of section 5 has been stated in the application in suit to have a date of filing more than twelve months before the date of filing of the application in suit, the Patent Office shall notify the applicant that the earlier relevant application will be disregarded unless, within one month, he supplies the Patent Office with a corrected date, being one which falls within those twelve months.