A club spokesman said: “It’s disappointing that we’ve had to make a change at such short notice.
“We’re sure all supporters will sympathise with what Orient fans have suffered in recent times. The club’s new owners will have had a lot to tidy up since the takeover, but it’s clearly unacceptable for us to be offered a youth team as our opponents for this fixture.
“Orient are now just one division above us and we need a more appropriate challenge ahead of our National League South programme.”
It’s understood that manager Alan Dowson and coach Martin Tyler are using their contacts to try to replace the fixture with one against a Championship club’s younger players a possibility.