Exactly.
Either he goes for top dollar in the summer, or we are promoted and he stays. What isn't happening is Southampton get him at the quoted price in January.
This.
And for what it's worth, I don't think the club would sell March at that price. I genuinely think they'd want more for an England U21 player who is beginning to look like one the best players in an unbeaten Championship leading side.
But if he does go, it will be for £9m plus add-ons...