Attack on Titan Staff Apologizes for Unfinished Episodes on 3 Stations

I think this is the reason why they were asking if there was any people interested in joining the animation team.

"The Attack on Titan production committee issued an apology on Wednesday for not finishing episodes 4 and 5 in time to air on three stations. Broadcasters FBS, Hokkaido TV, and TOS TV Oita only received parts of the episodes, resulting in a difference in content compared to what the stations MBS, Tokyo MX TV, TV Aichi, and BS11 showed.

The committee cited differing deadlines for broadcast stations as the cause, but promised to dedicate more time and staff to the production to prevent the issue in the future. Character designer and chief animation director Kyoji Asano posted an ad on Twitter last month to recruit animators to join the anime's staff.

The series is currently airing on MBS in Japan, and Crunchyroll and Funimation are streaming it as it airs in North America and abroad. "

http://www.animenewsnetwork.co.uk/news/2013-05-09/attack-on-titan-staff-apologizes-for-unfinished-episodes-on-3-stations

Well I honestly won't complain the animation has been outstanding. I don't mind waiting a bit more for superb animation. Although with more animators if it's possible to do it faster the better then.