Mr.Balaji/Panicker - Managers does not get the protection as enjoyed by the workmen. The Managers' terms of contract is governed by the general terms of the terms of appointment. Moreover, the role of a Manager is defined by targets and responsibilities and hence he cannot have remedy of working hours/holiday etc. However, the company/firm where they work should be covered by the local shops and establishment act, the establishment is bound by the regulation/restrictions for opening/closing etc. Even here, labour authorities wont take note of a Manager being working on a holiday. Please check your terms of appoint for more clarity on your terms and conditions.
Further if your nature work is purely of workmen nature and designated as a "manager" to avoid the purview of the rights available for a workman, you can claim the rights of a 'workman" . Again fighting on a thin line like this
would hardly yield any fruitful results!