User blog comment:Manuel de la Fuente/Attack on Titan Season 2: release date, facts, rumors, and everything we know so far/@comment-28004226-20160418185136/@comment-5774380-20160419014009

Read the paragraph after the one you are quoting:

"This is also consistent with the decision to wait until this year to launch the season, as the two arcs were recently completed at the middle of the last year, and the consequent work of adaptation would result in a 2016 release."

Also from the interview to Wit Studio's president at the Sakura-Con 2016:

Q: Given your short staff list, I assume the second season of Attack on Titan will be a long time in coming?

A: The guys are in the room working on Titan right now. Please be patient.