Question:  After what date are additions to each club's playing list allowed for the 121st season of the Austrailian Football League (AFL)?

Context paragraphs:
2014 AFL draft: The 2014 AFL draft consists of the various periods where the 18 clubs in the Australian Football League (AFL) can trade and recruit players following the completion of the 2014 AFL season.  Additions to each club's playing list are not allowed at any other time during the year.

2015 AFL draft: The 2015 Australian Football League draft consisted of the various periods where the 18 clubs in the Australian Football League (AFL) can trade and recruit players following the completion of the 2015 AFL season.  Additions to each club's playing list are not allowed at any other time during the year.

2017 AFL draft: The 2017 AFL draft will consist of the various periods where the 18 clubs in the Australian Football League (AFL) can trade and recruit players following the completion of the 2017 AFL season.  Additions to each club's playing list are not allowed at any other time during the year.

2016 AFL draft: The 2016 AFL draft consisted of the various periods where the 18 clubs in the Australian Football League (AFL) could trade and recruit players following the completion of the 2016 AFL season.  Additions to each club's playing list are not allowed at any other time during the year.

2011 Bohemian F.C. season: The 2011 season is Bohemian Football Club's 91st season in the League of Ireland and the club's 121st year in existence having played previously in the Irish Football League from 1902 to 1911 and 1912 to 1920.  Having finished 2nd in the league last year they club will play in the League of Ireland Premier Division under manager Pat Fenlon.  They will also compete in the FAI Cup, the League of Ireland Cup, the Setanta Cup, the Leinster Senior Cup and the Europa League (2011-2012 qualification) this season.

2017 Sydney Swans season: The 2017 AFL season was the 121st season in the Australian Football League contested by the Sydney Swans.

2017 AFL Grand Final: The 2017 AFL Grand Final was an Australian rules football game contested between the Adelaide Crows and the Richmond Tigers, held at the Melbourne Cricket Ground on 30 September 2017.  It was the 121st annual Grand Final of the Australian Football League (formerly the Victorian Football League), staged to determine the premiers of the 2017 AFL season.  Richmond defeated Adelaide by 48 points, marking the club's eleventh premiership, their first since 1980.  Richmond's Dustin Martin won the Norm Smith Medal as the best player on the ground.  The match was attended by 100,021 people, the highest crowd since the 1986 Grand Final.

2017 AFL season: The 2017 Australian Football League season was the 121st season of the elite Australian rules football competition.  There are 18 teams competing in the league, the same as the previous five seasons.  The first game was played on Thursday, 23 March, and the season concluded with the 2017 AFL Grand Final on Saturday, 30 September.

2017 Carlton Football Club season: The 2017 AFL season will be the 121st season in the Australian Football League contested by the Carlton Football Club.  The club's women's team also contested the inaugural season of the AFL Women's competition, finishing fourth.

2017 Collingwood Football Club season: The 2017 Collingwood Football Club season was the club's 121st season of senior competition in the Australian Football League (AFL).  The club also fielded its reserves team in the VFL, and a women's team in the inaugural AFL Women's competition.

Supporting paragraphs: 2017 AFL draft 2017 AFL season
Answer: 30 September