It is quite a seismic shift in UK Politics which tends to be very party controlled - this small (and growing group) have also become the 4th largest 'party' in the UK. In a Parliament in which government teeters on a knife edge of support that is quite significant.
HOW DOES THIS RELATE TO A LEVEL POLITICS STUDENTS?
This is a very good example of party discipline being undermined ; The powers of MP's / backbenchers; The change of party control in the Commons ; The limitations to the power of the whip.