There is no requirement by the Uk or Irish state for a passport but you need Id for flight / boat and some firms insist on a passport. I can’t see how they could refuse travel if the passport is valid and there’s no need to present one for immigration control. Aer Lingus and Ryanair have never checked mine in any depth either, just checking photo is me and name matches boarding pass (Ryanair’s t&cs actually exclude Uk Ireland travel needing the extra three months validity).
I’ve never been asked for a passport on arrival in Uk, and by plane you bypass passport controls anyway.
Passport control in Ireland will check your nhs covid pass and passenger locator form(online very easy to do). Venues , pubs, restaurants will also check the covid passes.
There is no requirement by the Uk or Irish state for a passport but you need Id for flight / boat and some firms insist on a passport. I can’t see how they could refuse travel if the passport is valid and there’s no need to present one for immigration control. Aer Lingus and Ryanair have never checked mine in any depth either, just checking photo is me and name matches boarding pass (Ryanair’s t&cs actually exclude Uk Ireland travel needing the extra three months validity).
I’ve never been asked for a passport on arrival in Uk, and by plane you bypass passport controls anyway.