It is 328 days from the start date to the end date, end date included, or 10 months, 24 days including the end date.
July/August 2009
Stage 5 - 2009 July 2010 2-7 was released on: USA: 31 August 2010
Post Grad - 2009 was released on: USA: 13 August 2009 (Hollywood, California) (premiere) Canada: 21 August 2009 USA: 21 August 2009 Germany: 3 December 2009 Australia: 1 January 2010 Ireland: 1 January 2010 UK: 1 January 2010 Brazil: 8 January 2010 (DVD premiere) Poland: 29 January 2010 Argentina: 9 April 2010 (DVD premiere) Spain: 16 April 2010 Japan: 2 July 2010 (DVD premiere) France: 7 July 2010 Finland: 9 July 2010 (DVD premiere) Italy: 9 July 2010 Sweden: 14 July 2010 (DVD premiere) Netherlands: 3 August 2010 (DVD premiere) Hungary: 6 August 2010 (DVD premiere) Turkey: 11 August 2010 (DVD premiere)
Framed - 2009 TV was released on: UK: 31 August 2009 Sweden: 10 August 2010 USA: 26 December 2010 Japan: 10 July 2011
July or August 2009 there's no sure answer.
The Outside - 2009 was released on: USA: 13 August 2009 (Los Angeles, California) USA: 24 June 2010 (premiere) USA: 20 July 2010 USA: 20 July 2010 (video premiere)
Kambakkht Ishq - 2009 was released on: India: 3 July 2009 Ireland: 3 July 2009 Netherlands: 3 July 2009 UK: 3 July 2009 USA: 3 July 2009 Japan: 4 August 2010 (DVD premiere)
104.4 weeks
The Sorcerer's Apprentice - 2010 was released on: Canada: 8 July 2010 (Fantasia Film Festival) Argentina: 12 July 2010 (Buenos Aires) (premiere) Canada: 14 July 2010 Kazakhstan: 14 July 2010 USA: 14 July 2010 Argentina: 15 July 2010 Greece: 15 July 2010 Israel: 15 July 2010 Kuwait: 15 July 2010 Philippines: 15 July 2010 Russia: 15 July 2010 Serbia: 15 July 2010 Colombia: 16 July 2010 Turkey: 16 July 2010 Indonesia: 21 July 2010 South Korea: 21 July 2010 Malaysia: 22 July 2010 Peru: 22 July 2010 Singapore: 22 July 2010 Thailand: 22 July 2010 Ukraine: 22 July 2010 Bulgaria: 23 July 2010 Sweden: 28 July 2010 Denmark: 29 July 2010 Netherlands: 29 July 2010 Estonia: 30 July 2010 Finland: 30 July 2010 Mexico: 30 July 2010 Norway: 30 July 2010 Poland: 30 July 2010 Romania: 30 July 2010 Hungary: 5 August 2010 Bosnia and Herzegovina: 6 August 2010 Iceland: 6 August 2010 Belgium: 11 August 2010 France: 11 August 2010 Switzerland: 11 August 2010 (French speaking region) Spain: 12 August 2010 Brazil: 13 August 2010 Ireland: 13 August 2010 Japan: 13 August 2010 Lithuania: 13 August 2010 UK: 13 August 2010 Italy: 18 August 2010 Czech Republic: 19 August 2010 Portugal: 26 August 2010 Uruguay: 27 August 2010 Austria: 2 September 2010 Germany: 2 September 2010 Switzerland: 2 September 2010 (German speaking region) Venezuela: 3 September 2010 Australia: 9 September 2010 China: 9 September 2010 Slovakia: 16 September 2010
Hoopworld - 2010 VG was released on: Argentina: 19 July 2010 Brazil: 19 July 2010 Canada: 19 July 2010 Colombia: 19 July 2010 Ecuador: 19 July 2010 Mexico: 19 July 2010 USA: 19 July 2010 Australia: 13 August 2010 France: 13 August 2010 Germany: 13 August 2010 UK: 13 August 2010
Aliens in the Attic - 2009 was released on: Kazakhstan: 30 July 2009 Russia: 30 July 2009 Canada: 31 July 2009 USA: 31 July 2009 Indonesia: 5 August 2009 Lebanon: 6 August 2009 UK: 12 August 2009 Malaysia: 13 August 2009 Ireland: 14 August 2009 Italy: 14 August 2009 Spain: 14 August 2009 Philippines: 19 August 2009 Argentina: 20 August 2009 Peru: 27 August 2009 Ukraine: 27 August 2009 Mexico: 28 August 2009 Panama: 28 August 2009 Venezuela: 28 August 2009 Australia: 3 September 2009 Greece: 3 September 2009 Singapore: 9 September 2009 Colombia: 11 September 2009 Turkey: 11 September 2009 New Zealand: 17 September 2009 Iceland: 18 September 2009 Poland: 18 September 2009 Czech Republic: 24 September 2009 Brazil: 25 September 2009 Egypt: 30 September 2009 Kuwait: 1 October 2009 Germany: 8 October 2009 Austria: 9 October 2009 Bulgaria: 16 October 2009 France: 28 October 2009 Sweden: 20 January 2010 (DVD premiere) Hungary: 28 January 2010 (DVD premiere) Netherlands: 6 April 2010 (DVD premiere) Japan: 4 August 2010 (DVD premiere)
April 28th 2010? Your conception date is roughly between Friday July 31st 2009 and Thursday August 6th 2009, give or take a few days