When the format was introduced before Christmas, there were technical concerns.
The limited format was introduced in an attempt to bring more balance to the environment.
The third format, clues and answers, was introduced in Series 3.
The current format was introduced for the 2010 season and consists of three stages.
In 2005, a new format of presenting the songs was introduced.
An entire new format was introduced and the coverage is different.
After 2004, a 22-teams format was introduced together with playoffs.
Here, many new formats of the written battle style were introduced.
Which is probably a late start, since the format have been introduced recently.
Also, during the third week, it took five points to win the round; this would become permanent when the second format was introduced.