Mundovela has now published the NoR for the SPanish Nationals.  There are 20 places available for Mistral Men (non-Spanish) and 30 for Mistral Women (non-Spanish).
The NoR is available at http://www.mundovela.com/esp/Campeonato/regatas%20previas/Campeonato%20España/anuncio_españa.htm
The entry date is the 15th July.