The clash was originally scheduled to take place in its usual midweek evening slot during the week commencing Monday August 13 but, with the approval of the Football League, it will now kick-off at 3pm.
It provides both Cheltenham and MK Dons with a full week to prepare for the opening of their respective league seasons a week later on Saturday August 18.
The tie will take place at the same time as the Olympic football men's gold medal match at Wembley, but officials from both clubs are confident the fixture will still attract a big crowd at Whaddon Road.
The two sides met in the first round of the competition last year, with MK Dons running out 4-1 winners.
