The 23-year-old is yet to play a game this season after sustaining a stress-related foot injury in mid-February.
Allen had returned to training with the club last week and was aiming for a return to action in the coming fortnight.
However, the club has listed the young forward as 'TBC' in their most recent injury update, with AFL.com reporting that Allen will not return to first-team action until after the mid-season bye.
Eagles head of health Mark Finucane stated that the club are working with Allen to get him back to full fitness, but are not willing to rush the process.
"Oscar we're taking a conservative approach with," Finucane said.
"Really important young player for us. Still just working through what his build is to return to play."
Allen also discussed the issue himself on TAB Radio, explaining how he feels progress is being made slowly and is remaining positive on the issue.
"I can see it's getting closer. The light at the end of the tunnel is almost there," Allen said.
"It sounds like a bit of a broken record, I'm still building my training loads."
Allen was taken at Pick 21 in the 2017 NAB AFL Draft and has kicked 66 goals in 59 games since his debut in 2018 for the Eagles.