[Padna]

AFAIK, those resident in NI but working in the ROI are still able to access all NHS services in NI. They are also eligible to apply to the HSE for an ROI medical card if their income is below the normal limits.

If they pay PRSI in the ROI (as they normally will if they work full-time there), their EHIC card (for travelling to other EU/EEA countries) should be issued by the HSE rather than the NHS (as it's based on where one pays social insurance rather than on residency).