I know (knew) that Merchant seamen can be paid into an Offshore Bank, Jersey etc, and you only get taxed when you bring money into the country.

If you are doing 2/3 and 2/4 then presumably you will be coming back to the U.K when not working, that means you are only out the country for 2 or 3 weeks.

Ask at the interview, they will know all about it.

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