This chapter is applicable to all group health insurance policies or contracts issued or delivered in this State to the employer of the insured which provide hospital, surgical, medical, or major medical benefits on an expense-incurred basis whether issued by a nonprofit health service plan or by any other insurer, and to all group policies or contracts issued or delivered in this State to an employer by a health maintenance organization certified under Health-General Article, Title 19, Subtitle 7, Annotated Code of Maryland. This chapter is applicable to any policy or contract issued on or after the effective date of this chapter, beginning with the date of issue of the policy or contract. This chapter is applicable to any policy or contract issued before the effective date of this chapter, beginning on the first annual renewal date or the first anniversary of the date of issue of the policy or contract occurring on or next following the effective date of this chapter.