Talk:Fall 2016 Event/@comment-93.221.239.81-20161125030526/@comment-26351458-20161125031953

The exact rules have not been 100% confirmed. However, IF that air raid was indeed the last requirement, the node would have opened up before you proceeded to whatever node you were about to go to. e.g. Air raid occurs before going to node G -> white text -> node opens -> choose formation for node G. This happened to me, after my 5th white text (2nd perfect defense) on hard mode.

This suggests that you probably didn't fulfill all requirements, even if you actually did do everything. From most comments regarding E-5E, it seems to be 1x S-rank at node A, 1x S-rank at node C, and 2 white texts (doesn't have to be a perfect defense).