Once you have joined the MRS you are required to keep contributing as long as you are working in the maritime industry.
After you have contributed to MKS for twelve months you can apply to the IRD for a contributions holiday. The contributions holiday can be for as little as three months or as long as five years. They can also be rolled over. If you are also a member of MRS, taking a contributions holiday may affect your entitlements under that scheme, particularly your entitlement to a death benefit.