This is due to Manchester City's participation in the Champions League. Pep Guardiola's side were due to face Everton that afternoon in front of the Sky Sports cameras but their Champions League group game against Dinamo Zagreb has been arranged for Tuesday, 1st October.
That means they will now travel to the Toffees on Saturday, 28th September at 5.30pm (BST). That had been the date and kick-off time for United's trip to the King Power Stadium, which was already set to be shown live on Sky Sports, so the two slots have effectively been swapped and the broadcaster will still show both matches.
Tickets had not yet gone on sale for the Leicester game. The two sides met at St. James' Park in the Carabao Cup on Wednesday night, with the Foxes winning a penalty shoot-out following a 1-1 draw.