The Long War Journal assesses the recent reports and concludes:
There is no question that Saif al Adel, Abu Mohammed al Masri and Abu Khayr al Masri are among al Qaeda’s most senior leaders....the freed jihadists may serve another purpose. Jihadists on social media have circulated a rumor suggesting that al Qaeda plans on relaunching a new branch inside Iraq, in direct competition with the Islamic State. The al Qaeda leaders released from Iran are well-positioned to lead this effort....These men could argue the opposite, saying they, and al Qaeda, are Zarqawi’s true heirs.
Link:http://www.longwarjournal.org/archiv...-from-iran.php

Now if that assessment is correct the Iranian "release" makes sense in countering ISIS. Indeed a certain US general has mooted using AQ to counter ISIS; strange world sometimes.