From 1948 onwards a steady trickle of boats continued to arrive in Britain. Remember the government putting the arrivals of the first boat up in an air raid shelter in Clapham. The closest jobcentre to this shelter was on cold harbour lane, Brixton. Here the new arrivals could find work or claim unemployment money ( the welfare state was also bourne in 1948). And so the black community started to grow in Brixton.
After a couple of years another community started to grow in Notting hill. This was down to ruthless landlords, people like Peter Rachmann. Who treat these new arrivals like pigs. Forcing them to pay over the odds for inferior living conditions, often men sleeping in rooms with people they had never met, but by now most decent landlords wouldn't let their property to blacks.
With work in short supply by the mid 50s and the continued arrivals, the people were calling for the government to end the open door policy. Groups like the British defence league started up and KBW. Tensions were building and by the late 50s whites had had enough. In Nottingham there was a big gathering of whites who wanted to take matters into their own hands. The next day, 4 days of rioting ( by whites) started in Notting hill, 1958.
And so, the first 10 years of immigration for black people had not gone smoothly, maybe the first 2 or 3 years were ok but as the communities grew and the differences of races became apparent, there was unease.
By 1961 the government caved in and effectively ended black immigration. A new law which stated any new arrivals must have family that were born in Britain was obviously aimed to stop black immigration. The end of the open door policy.