No, for several reasons:
1. Immigration can always just be completely stopped whenever necessary. That's the luxury of being an island nation.
2. The predominant trend in established faiths in Britain is one of substantial numerical decline. If anything, we will be a secular nation by the 2050s, if we aren't already.
3. The rate of births to Muslim parents has consistently fallen since the community was first established here, and as Muslim countries continue develop there will be signficantly less impetus for many Muslims to move to a First World country.
At any rate, I don't particularly care which religion is dominant, as they're all the same and full of ********. I do think that there is probably a cut-off point to immigration from all demographics, whatever religion, race, etc., and that Europe is fast approaching that; consequently I believe that the EU should seal it's borders to potential immigrants with non-EU states [exceptions being Switzerland, Norway and the microstates]. We need time to adjust European societies to the new realities of multiculturalism, and we also need to realise that, from a more pragmatic point of view, states have a relatively fixed potential carrying capacity before they become unsustainable in terms of the amount of resources they consume. Britain's infrastructure, and that of much of Europe, is groaning under the pressures of immigration, and we already consume more than our fair share of global resources.