I am starting this a bit early, but only because this is already being discussed on another thread.
Here is my understanding of whose contract is up in June:
Scott Davies, Luke Pilling, Partick Wharton, Steve McNulty, Eddie Clarke, Jay McEveley, Jay Harris, Jake Kirby, Jeff Hughes, James Wallace, Mitch Duggan, Jack Dunn, Elliot Rokka, Devarn Green, Darnell Cole, Drissa Traore, Andy Cook, Connor Jennings and Andy Mangan.
The following are tied up for another year:
Evan Gumbs, Liam Ridehalgh, Richie Sutton, Adam Buxton, Ben Tollitt, Oliver Norburn, James Norwood, George Waring and James Alabi.
I would imagine most of the first list have already been approached for an extension but have either decided to leave (like Hughes) or are waiting for better terms or to find out which league we are in next year. As far as I know, only Evan Gumbs has extended his contract during the season.