As discussed time and time again for many years SOU is not targeting penny pinchers paying a few quid to fly the awful RYR.
You could see from the extremely jealous and mean spirited letters BOH submitted to object to SOU’s runway extension that they know SOU with a low cost operator will be much more successful than them.
So I will say it again, BOH is completely irrelevant to SOU. It's a poor airport, poorly located, with poor transport links that gets by with Poundland flights.
Yes, let's not "stir up the BOH v SOU debate again" !