"He is waiting for the powers that be to give a date," the source said.
Harvey told reporters in late May that he expected to be throwing off a mound early last week, but Sandy Alderson put it on hold.
In the meantime, he continues to throw off flat ground.
In addition, Alderson said last week that, although Harvey may wish to make five to seven starts this season, the Mets want him to wait at least 11 months after his Tommy John surgery before he pitches in a game, which is standard protocol and the doctor recommended time frame.
Harvey had his surgery on Oct. 22, 2014, which leaves only the final week of September for him to pitch in the regular season.
Harvey has said he wants to go in to the off season knowing he’s capable of pitching in a game.
“I think there are other ways that we can provide that kind of peace of mind (for him), whether it’s in instructional league or some other setting,” Alderson said. “So, that’s yet to be determined.”
The organization’s instructional league runs September in to October.
Harvey said he was caught off guard when the team stopped him Monday from throwing off the slope of a mound.
“They have a higher power,” he said, noting that he has yet to be told why his throwing session was postponed and when he’ll throw again. “I don’t know if somebody talked to a doctor or whatnot and they felt that things needed to slow down."