The MOM website even specifically list “Chartered Accountant” as an exception to the people covered by the Act. If you didn’t know this, you’re probably quite young huh.

Who is a manager or executive

In general, managers and executives are employees with executive and supervisory functions.

Their duties and authority may include one or all of the following:

Making decisions on issues such as recruitment, discipline, termination of employment, performance assessment and reward.
Formulating strategies and policies of the enterprise.
Managing and running the business.
They also include professionals with tertiary education and specialised knowledge or skills whose employment terms are like those of managers or executives. For example:

Advocates and solicitors
Chartered accountants
Practising doctors and dentists