The son of former Hammers and Tottenham midfielder John Moncur, George is a regular with the U18s and has tasted reserve-team action.
"I have enjoyed [the summer]," Moncur told WHUTV about his fast-track progress. "It has been really good. I have liked stepping up and trying to cement my place in the reserves.
"I believe in my ability and if I carry on doing the good things I should step up but we will see how it goes. My dad tells all the time to keep working hard, keep doing the good things, and keeping the ball."