He was taken off the transfer list in the summer and his scoring prowess has attracted attention from the likes of Bolton Wanderers and Newcastle United.
But Grayson has again insisted that he will not be tempted to cash in on the 25-year-old in the New Year as he looks for Beckford to spearhead the club's promotion push.
"I'll be bracing myself for calls in January, but he won't be going anywhere," stated Grayson. "Jermaine came off the transfer list in the summer and the chairman has promised me that he won't be going anywhere.
"If he walks away in June and we've been promoted then it'll be happy days for us because we've achieved what we need to do.
"If he leaves then that's entirely up to him. That's the risk we're running, but I'm sure he'll concentrate and keep getting his goals."