Grayson told the club's website: "I've said all along that I would evaluate the squad at the end of the season. I'd like to thank them for their efforts.
"I've spoken with the players, and I have to say that they have both been excellent professionals since I arrived in December.
"Up until last Thursday we didn't know what our league status would be for next season.
"I felt it was important that decisions were made as quickly as possible after that to allow us to move forward as a club and to give the players the best possible opportunity.
"I am looking to strengthen what we have here and while players will be coming in, departures are also inevitable as we look to prepare in the best manner possible for next season."