11. A driving licence issued or renewed under this Ordinance, shall, subject to the provisions contained in this Ordinance as to the cancellation of driving licences and disqualification of holders of driving licences for holding or obtaining driving licences, be effective without renewal for a period of twelve months only from the date of issue of the driving licences or, as the case may be, from the date with effect from which the driving licences are renewed under section 12, and the driving licences shall he deemed to continue to be effective for a period of fifteen days after the date of its expiry: Provided that if the licensing authority has reasons to believe that the applicant has been employed abroad or has signed a contract for employment abroad, it may renew a professional driving licence for a period not exceeding three years at a time on payment of the fees specified under sub-section (4) of section 12 for each such year: Provided further that where the applicant so desires, a non professional driving licence may be renewed for a period of three years at a time on payment of fees provided under sub section (4) of section 12 for each such year subject to the condition that, on becoming unfit to drive by virtue of disease of disability, the holder shall surrender the driving licence within fifteen days, to the licensing authority within whose jurisdiction he resides or, to the licensing authority which issued it.