first off, if ye do protest, the best of luck.
but, sadly, unless the organisers are legal and hard working and seek better rights for immigrants (eg access to training, work conditions, integration and or toleration of race etc) then ye are wasting yer time.
like it or not, like any country (see recent itv1 debate with cameron, brown and nick ? on non eu immigration), the plight of the immigrant and in particular the illegal immigrant at this time, is way down the list of priorities of the people and government.
the governement will be going so don't worry about that. but the next shower won't be much different, remember what leo valdkar once suggested? populism on this matter will sadly take front row, to the determent of long term matters for the country itself and the non eu immigrant
what are you looking for anyway? better rights, fairness, support? or open boarders?