Question: The Fireworks incident, was a very serious case of Football hooliganism which took place on Easter Sunday, on which date, after a 30 minute recess in which marketing director Edwin van der Sar addressed the crowd?

Context articles: Edwin van der Sar
Staafincident
Easter Rising centenary parade
Anders Lindegaard
2011–12 AFC Ajax season
Frans Hoek
Fireworks incident
David Endt
Kim Yong-dae
Easter Act 1928

Edwin van der Sar OON (] ) (born 29 October 1970) is a Dutch former professional footballer who played as a goalkeeper.
 During his career he played for Ajax, Juventus, Fulham and Manchester United.
 He is the second most capped player in the Netherlands national team's history.
 He currently works as the chief executive officer at Ajax.
 He came out of retirement to play for Dutch amateur team VV Noordwijk.
The staafincident (Dutch, "rod incident") was a very serious case of Football hooliganism which took place 27 September 1989 in the De Meer Stadion of Dutch football club Ajax Amsterdam.
 During a home match against Austria Wien the Austrian goalkeeper Franz Wohlfahrt was struck by a metal rod which was launched onto the pitch by the Ajax hooligan firm F-side.
 Ajax conceded the match regulatory and as a result were excluded from competing in European football for a year.
The Easter Rising centenary parade took place in Dublin city on Easter Sunday, 27 March 2016 to commemorate the Centenary of the Easter Rising.
 It involved all branches of the Defence Forces, including the Army, Air Corps, Naval Service and Reserve Defence Forces, as well as the Gardaí, Dublin Fire Brigade, the National Ambulance Service, the Irish Coast Guard, the Irish Prison Service and Customs, the Red Cross, the Coast Guard, the RNLI, the Civil Defence Ireland and St John Ambulance.
 The parade was one of the largest of its kind ever held in the state, involving over 3,700 military personnel, 78 vehicles and 17 aircraft.
 The events were broadcast on RTÉ television and it is estimated that around 1 million people viewed the parade across the streets of Dublin.
 The parade commenced at 10:30am from St. Stephen's Green and made its way along Dublin before stopping at O'Connell Bridge for the main Easter Sunday Commemoration at the GPO.
 Following the ceremony, the troops marched past the GPO in O'Connell Street before finishing at Bolton Street around 3pm.
Anders Rozenkrantz Lindegaard (] ; born 13 April 1984) is a Danish footballer who plays for English club Burnley as a goalkeeper.
 He began his career with his hometown club, Odense Boldklub, but a lack of first-team opportunities led to a move to Norwegian club Aalesund in 2009, with whom he won the Norwegian Football Cup.
 After winning the Goalkeeper of the Year award in both Denmark and Norway in 2010, Lindegaard was signed by Manchester United, where he played for five years as a back-up to Edwin van der Sar and David de Gea.
 He moved to West Bromwich Albion in 2015, but was unable to break into the team and joined Preston North End in January 2016, initially on loan.
 He joined Burnley in September 2017.
During the 2011–12 season AFC Ajax participated in the Dutch Eredivisie, the KNVB Cup, the UEFA Champions League and the UEFA Europa League.
 The first training took place on 27 June 2011.
 The traditional AFC Ajax Open Day will be held on 3 August 2011, followed by a testimonial match for the retired former Ajax goalkeeper Edwin van der Sar.
Frans Hoek (] ; born 17 October 1956) is a Dutch football coach and former player.
 As a player, he was a goalkeeper for FC Volendam for more than a decade, before going into coaching as an assistant to Louis van Gaal at club sides AFC Ajax, FC Barcelona, FC Bayern Munich and Manchester United, and the Netherlands national team.
 He also worked for the Poland national team under fellow Dutchman Leo Beenhakker.
 He has worked with goalkeepers including Edwin van der Sar, Stanley Menzo, Víctor Valdés, Vítor Baía, Pepe Reina, Robert Enke, Łukasz Fabiański, Thomas Kraft, Michel Vorm and David de Gea.
 Hoek is widely regarded as one of world football's foremost goalkeeping mentors.
The Fireworks incident (Dutch, "Vuurwerkincident") was a very serious case of Football hooliganism which took place on Easter Sunday, 20 April 2014 in De Kuip, Rotterdam, during the KNVB Cup final match between AFC Ajax and PEC Zwolle.
 Mass amounts of fireworks, flares and smoke bombs were launched into the penalty box around Ajax goalkeeper Kenneth Vermeer in the early minutes of the match, which had been thrown onto the pitch by the Ajax hooligan firm VAK410 twice in the early build up of the game.
 After a 30 minute recess in which marketing director Edwin van der Sar addressed the crowd, Ajax would go on to lose the match 5–1 to Zwolle.
David Endt (born 6 May 1954) is a Dutch sports journalist, author and columnist.
 From 1997 to June 2013 he was the team manager of Ajax before Technical Director Edwin van der Sar expressed that his services would no longer be required within the club.
Kim Yong-dae (born 11 October 1979) is a South Korean football goalkeeper who plays for the K League Classic club Ulsan Hyundai.
 Despite not playing for South Korea since 2008, he is considered one of South Korea's best goalkeepers even to the point where he has been nicknamed by fans as "Yong Der Sar" in reference to former Dutch goalkeeper Edwin van der Sar of Manchester United and the Netherlands.
The Easter Act 1928 (c. 35) is an Act of the Parliament of the United Kingdom passed and enacted in 1928 concerning the date for Easter, but has never come into force or become implemented.
 The effect would be to establish Easter Sunday as the Sunday following the second Saturday in April, resulting in Easter Sunday being between 9 April and 15 April.