Just reading about a potential flame that has been started in Northern Ireland that I freely admit had not crossed my mind. It seems the 'Get Ready' site explains that all UK registered cars in EU countries will have to have a GB sticker.

It does not need more than a few moments thought to realise how inflammatory that could be for Republican supporters in Northern Ireland. The genius of the Good Friday Agreement lies in the way differences between the two sides are de-emphasised wherever possible. And then we introduce a bureaucratic rule which requires people to identify as the group they are not - not everyone can afford to change their car to buy one registered elsewhere, or adds another means for the Loyalists to proclaim they are wedded to the mainland.   And if people do buy cars registered elsewhere so they do not need the GB sticker, it becomes an even more potent symbol.