A plan includes any definitive insured or properly self-insured program, effectively providing for employees cash disability benefits that differ from the benefits required to be provided under section 204 of the Workers' Compensation Law either as to rate, waiting period, maximum or minimum benefits, accrual of eligibility or termination of eligibility, duration of benefit period, or in any other respect. A plan may also provide benefits other than cash disability benefits. A plan may provide benefits for all of the employees of an employer, or for some class or classes of his employees.