There has very evidentially been a lowering of the wage structure at the club since he signed.
They have signed several players in the past, on contracts which they have later decided were too high and so have later either sold or released them at the end of their contracts.
Why would Cantwell be different?
Do you think they will be tying him down to an extended deal? The evidence of the last few years suggests not.
If not, then like Travis, Brittain, Hyam, they will be looking to cash in for what they can get in the next 6 months or so.