Yes it’s what ever is the cheaper option I had a 2008 525d LCI (3.0) which was registered in January of 2008
Technically if that was an Irish car the tax would have been €1494 at the time but because it was an import the tax was CO2 based and was €750 as this was the cheaper option it’s what ever benefits the car at the time. One thing the revenue dont screw you on here ��.. and as for vrt on an M3, my mate imported a 2009 E90 M3 in December ‘20 and paid €9500 in January. Had to be presented and assessed first as it was not on the system for quotation.
https://www.motortax.ie/OMT/pdf/faqs_co2_en.pdf
Here’s a bit about it