The current plan is for the rest of the Magic World arc to be told with a motion picture coming out next year.
To me, the way the OAD and movie is being planned out (with the OAD starting all the way from the beginning of the Magic World arc) is a bad idea of telling the story in anime form. The two main reasons:
1. Personally, I hated the way the Magic World arc began (with everyone being separated, and most of the focus going towards Negi taking part in a tournament just because one of the students who decided to sneak into the world ended up getting sick and caused herself and two other students to get sold into slavery).
2. Cramming everything that takes place in the Negima manga from volume 24 to the current positsion in the manga (which is currently at volume 34) is going to result in a big mess.
Personally, if I was in charge of the anime, I would have summarized the first three-and-a-half volumes (save for the chapters focusing on Yue with amnesia, which will still have its own OAD) at the beginning of the first OAD, and have the first one focus on