Barnsley's Championship fixture against Reading next month has been forced to be moved due to a backlog in the Carabao Cup.
The Reds are yet to play their second round tie in the competition against Derby County, due to the postponement of the Rams' previous round game with Grimsby which they went on to win.
That cup game has now been scheduled for September 12 at Oakwell, meaning that the proposed league games have had to be rearranged with no new date set.
Derby were due to play Ipswich on the same night.
The EFL released a statement, saying: "The EFL would like to apologise to the Clubs involved and importantly the supporters of those teams involved for any inconvenience caused. However, the need to move the tie forward a week is required due to limited flexibility in the fixture schedule alongside the fact that the winners of the Round Two tie have been drawn against Tottenham Hotspur, who have the added complication of being involved in four competitions, including the Group Stages of the Champions League."