The NFL will release the full schedule for the upcoming 2014-15 season on Tuesday, April 22, according to Mike Florio of Pro Football Talk. The league may also wait until the 23rd or the 24th, but Florio reports that, "for now," the plan is to unveil the full schedule Tuesday.
The variable dates presumably has something to do with TV slots on both the NFL Network and ESPN. Like last year, both networks will want to make a spectacle out of the unveiling, which could mean a prime-time release with analysis and hype. With network schedules the way they are, it's likely that the NFL hasn't yet decided on an exact date.
All we ever know about the schedule's release is that it typically occurs prior to the NFL Draft. With said draft being moved to May this year, that means the schedule announcement can be pushed back further than usual. The league has an extra two weeks to add finishing touches or plan an announcement show.
We already know who plays whom and where the games will take place, we just don't know when. We may know everything on April 22.