The status quo was challenged by a federal official with a letter published in the football columns of La Gazzetta dello Sport in February 1912: according to him, there was no movement between the Prima Categoria and the Seconda Categoria, which had to bear the expenses of an entire season only to see them wasted by a single match against the reserve teams of the larger clubs.The new introduced regulations, strongly supported by the secessionist Italian Football Confederation (CCI) (which applied them starting in the 1921–22 season) and approved along with the Pozzo Plan, involved the division of Italy into two large geographical areas, managed by the North and South Leagues, with a sharp cut at the center of the country.As a result, the Seconda Divisione experienced two different sets of rules, due to the stark geographical and organizational differences: in the North, the league was organized outside the regional framework directly by the Lega Nord, while in the South, it was still managed by the Regional Committees because the distances and means of transportation didn’t allow for interregional league management.The first teams to be relegated (1921-22 season) were Vicenza and Inter Milan even if, after the CCI reunion with FIGC, the regulations were changed, and Venezia was demoted instead of the Milanese club.In the north, the new competition started in the 1922–23 season with 48 teams divided into six groups, structured at the interregional level but still vaguely corresponding to the jurisdictions of the regional committees.The far-reaching reform envisioned by the Viareggio Charter was completed in 1928 by the new FIGC president, the fascist politician from Bologna, Leandro Arpinati.The two-group formula would have reduced the high operating costs of participating in the second-tier league and given more representation to the central and southern teams.[4] The first edition saw 18 teams registered, a format that remained unchanged until the 1933–34 season, when an attempt was made to divide into two groups based on geography (west and east).However, this experiment was unsuccessful, and in 1935–36, the original model was reinstated, which, except for an attempt to reduce the number of teams between 1936 and 1938, continued until the break caused by World War II.It was the consequences of the so-called "Caso Catania" in the 2003–04 season that disrupted this consolidated tradition and brought the number of participating teams to a record high of 24, later reduced to 22 the following year.The original formula provided for the participation of four teams (from 3rd to 6th place) who faced each other in semifinals and finals (both based on home and away matches).As a result, the number of clubs participating in the promotion play-offs could vary, and thus the structure of the tournament changed depending on how many teams were involved.Furthermore, in the 2013–2014 season, Serie B introduced a single top sponsor for all teams participating in the league, which appeared on the back of the players' jerseys for the first time.