I don't have any specifics on Mercosur countries with me today, but without a doubt there's going to be a significant amount of support provided to the Argentinian wine industry, given its size in that country. They own their entire market, so if they weren't able to export they'd have to cut down their production. Their government will support them significantly to move that surplus volume out of the country.
On May 1st, 2018. See this statement in context.