The Italy international has not started a game since the restart, with reports claiming Juventus are lining up a bid for his signature.
18-year-old Gilmour was picked to start in the 3-2 win over Palace, which inevitably forced Lampard to field questions about Jorginho's future.
He said: "I thought Billy did pretty well. I wasn't overly delighted with our midfield today. I think considering how they have played in recent games and how slickly we have moved the ball in recent games and rotation, I thought we held onto it a bit long today.
"He trains like that as well, so does Jorginho, he trains really well. Little moments or my opinion of how I look at the game mean I have to make difficult choices through the games.
"It doesn't mean anything for the future of Jorginho, Gilmour or anyone else in the team, or on the impact that Jorginho had on the team in calming the team down with his passes at the end.
"I know he can give us that and he will continue to give us that."