As detailed in my reply to Parliamentary Question No. 523 of 9 April 2019, there are some UK categories known as ‘National Categories’ that only apply in the UK and they are not exchangeable. For example, in the UK if you passed your test for category B (car) before 1 January 1997, your licence would show entitlement to C1 and C1E (trucks) and D1 and D1E (bus) categories. These categories are given with restrictions identified by codes.
The C1E category with a restriction code 107 on it entitles the driver to drive a C1E vehicle provided the combined weight of the trailer and the towing vehicle does not exceed 8.25 tonnes/kg. In Ireland the combined weight of the C1E is 12 tonne/kg. Therefore we do not have an equivalent to exchange this category for. The D1 and D1E categories with a restriction code 101 on it only allows the driver to drive a vehicle not for hire or reward. We do not have the corresponding category so cannot exchange it. Code 101 and 107 are UK codes and are not available in Ireland, and so can not be converted.