Holders of UK driving licences who are resident in this jurisdiction are allowed to drive here on those licences until the end of the transition period 31 December 2020. They will not be entitled to drive here on those licences after that date.
Since before the original Brexit deadline in March 2019, the RSA has been encouraging holders of such licences to exchange them, and many have done so. I would encourage any holders of UK licences who are resident in this jurisdiction and who have yet to exchange their licence for an Irish one to do so as soon as possible.
Insurance companies are private bodies, and neither I nor my Department has any power over their decisions. However, as holders of UK licences who are resident in the jurisdiction will not be able to drive legally on UK licences after the end of the transition period at the end of this year, it is understandable that insurance companies would not cover them to drive on those licences. The solution for people in this situation is therefore to exchange their licences as soon as possible.
Where a person is the holder of a UK licence and resident in the UK, they may still drive here on their UK licence after the end of the year on a visitor basis. They will need insurance, and should check with their insurance provider to confirm that their cover extends to this jurisdiction.