There was much consternation by the conservative press after the census results indicated that white British are a minority in London. Although that was slighly misleading reporting (it did not follow that any other ethnicity was a "majority" only its own), it did indicate that white people were moving out of London.
The conservative press chose to interpret that as a "pushing out" of white people by an influx of other ethnicities (or even a "takeover" by cultures with higher birth rates). However, the BBC study today suggests the opposite: white British people who had done well in London chose to move out to the country; the younger, working population is now more diverse, consisting of both immigrants and non-white British who moved to London to work. Conversely, the number of white British in many areas outside London saw a significant increase, which means, I think, we can dismiss any notion of a dwindling white population in Britain as a whole in comparison with other ethnicities.
I really don't see any problem with that; it sounds positive to me and is a reflection of what London has always been about. People coming in from abroad to work. What is interesting is that the people who complain the loudest about it are those who don't actually live and work in London; those who do, don't seem to mind. Quite the opposite.
But those who do mind about keeping a white majority in Britain can now, I think relax.