The 2015 Segunda División play-offs took place in June 2015 and has determined the third team which will be promoted to which season that started on 21 August 2015 and concluded on 15 May 2016?
2015–16 La Liga: The 2015–16 La Liga football season (known as the "Liga BBVA" for sponsorship reasons) was the 85th since its establishment. 2015–16 La Liga:  It started on 21 August 2015 and concluded on 15 May 2016.
i don't know