Riordan is the only one who they might try and move on if...

Riordan is the only one who they might try and move on if they get a decent offer. Caldwell possibly going to Celtic is the other one, but I think that is likelier to happen at the end of the season. They're all playing regular, top-team football so there's no great need for them to leave. One or two of the bigger clubs might let their players go on loan to smaller clubs and Kilmarnock might be on the lookout for a striker now that Boyd's gone.