An exception to the requirement that an employee, whether full-time, part-time, permanent or temporary, will qualify as a tipped employee only if he customarily and regularly receives more than $30 a month in tips is made in the case of initial and terminal months of employment. In such months the purpose of the provision for tipped employees would seem fulfilled if qualification as a tipped employee is based on his receipt of tips in the particular week or weeks of such month at a rate in excess of $30 a month, where the employee has worked less than a month because he started or terminated employment during the month.