In this new development, teams will be allowed to call up a 13th player in addition to the 12 originally scheduled for the Olympic Volleyball competition. This will give teams the flexibility to replace a player who may have to withdraw from the tournament. 

These reserve players, if not actively participating, will be designated as "non-competing athletes." They will be accredited for the Olympic Games and can only compete if one of the initially selected 12 players initially selected suffers an injury or illness that prevents them from competing. 

Starting from Paris 2024, if a player suffers an injury or illness that prevents him/her from competing, he may be replaced by the reserve. However, the substitute will be disqualified from further participation, effectively being dropped from the squad. In other words, there won't be 13 players available per match, with a final selection of 12 at the time of the competition, as was the case at World Cups decades ago. 

The 13th athlete will be able to attend matches and train with the team but won't be accommodated in the Olympic Village unless the respective National Olympic Committee provides additional and exceptional support. Volleyball matches will take place from the day after the Opening Ceremony on 26 July 2024 and will run for almost the entire Olympic calendar, with events taking place from 27 July to 11 August at the South Arena in Paris.

Another change in volleyball for the upcoming Paris Games is the qualification process and grouping. Instead of two groups of six teams each, there will be three groups of four teams each. The top two teams from each group and the best two third-placed teams will advance to the quarter-finals, followed by a play-off to determine the champion. 

This modification will result in fewer matches, mirroring the adjustment made in basketball at the past Olympic Games. Teams advancing to the medal round will now play a total of six matches, rather than the eight that will be played until Tokyo 2020. 

Following last year's qualifiers, there are still five places to be decided for Paris 2024. These spots will be determined by the rankings in the regular phase of the Volleyball Nations League (VNL), finishing on 23 June. The matches in the first half of the year will be crucial for the non-qualified teams, with priority given to countries from continents that have not yet qualified their teams for the Pre-Olympic Tournament.

The teams that have already qualified for Paris 2024 are as follows:

Men's Volleyball:

France (host), Germany, Brazil, United States, Japan, Poland, and Canada.

Women's Volleyball: 

France (host), Dominican Republic, Serbia, Turkey, Brazil, United States, and Poland.