I think any of them in the final year of their contract will be subject to bids. That's why not sorting these out when we were in the PL is another dumb move by the club. Now relegated and with decent players into their last year of contract it is an uphill battle to keep them.
I can see us starting the season without Chester, Brady, Huddlestone, Hernandez, Jelavić and N'Doye. We've seemingly nothing in the pipeline and the season start is on the horizon - new players should participate in some pre season games/training, so at least come the start of the season we don't have 11 strangers on the pitch.
There's a stark reality that this season will be more about battling to beat the drop than challenging for honours.