Sometimes this site works against posters when people of limited knowledge weigh in with opinions as opposed to fact.
Irish corporation tax rate is 12.5%, the UK are bringing their rates down to roughly 16% over the next few years ... but they're not near the 12.5% for a few years. The rest of your query could involve a few pages of analysis so I couldn't hope to capture it all here, but lets give it a go ...
You can keep working through your UK Co. You could be tax-resident in both countries - the Double Tax Treaty will sort that out -but you could be liable to PAYE in both countries, this requires some immediate professional advice - which you won't get here (you need to know days working in which jurisdiction, the type of work, days of travel, type of UK accommodation .. ..)
The advantages of Personal Service Companies in the UK are being restricted in the latest Budget - I don't know what those restrictions are - but the advantages for companies such as yourself are a tax-arbritrage on VAT, reduced income tax on dividends. (If you don't know these already, likely you never got professional advice when incorporating yourself).
In the end/long-term; you will ultimately pay the equivalent of Irish tax at the marginal rate (which refutes RBs advice, unless you leave money in the UK company -but I'm unclear myself as to implications/savings of this).