Why please? Is it because of 3 year continuity ? Or will i have to wait for another 4 years to apply?

Hi, My situation is bit different. I came to uk in 2006 with my wife 1st child born in 2006 end. We came in work visa. We went back in 2007 when 1st child was 7 months. My wife had second child in 2009 outside back home. We came back to uk in 2011 in student visa. Now my children are 7 and 5 schooli...