Application for renewal or increase of grade of license shall be made by each pilot in person before the commissioners at a meeting of the board held not more than 30 days prior to the expiration of the license of such pilot. Any pilot applying for an increase of grade of license shall be required to submit a list of the names of the vessels piloted during the year, stating the dates and nature of service rendered, such as pilotage inbound, outbound, or transport, and the drafts of the vessels. Any pilot applying for renewal of license shall be required to submit a memorandum indicating the number of vessels piloted during the year by categories—inbound, outbound or transport. The memorandum shall also indicate, by dates, periods of more than five days when pilots do not work while on vacation, sick leave, or for other reasons. In addition, the pilot may be required to pass an examination prescribed by the board.