It's still a month away.
Ordinarly you'll hear of time changes about a week out for most North American airlines. Any earlier than that and people start getting upset that they get too many e-mails and messages from the airline. It's a Catch-22. We're damned if we tell you and damned if we don't. Indeed, I've overheard passengers complaining they were not told about a flight change. When the airline demonstrated both an e-mail and a text were sent, the passenger complained they never check their e-mail and the text was sent to the wrong number. A number the passenger inputted all by themselves. Even doing our best, airlines just can't win.
2. Flight number changed.
This happens from time-to-time. Your ticket is based on your PNR (booking reference number) not the flight number. A PNR is specific to a date and sector, where a flight number is normally specific to the run, irrespective of date. Consider a conversation where an airline employee says "Flight 123" and the response is "when?" The same conversation is held with "PNR ABCDEF" and the response is "what's the problem?" It's just quicker on the airlines end, hence why you were not told...but would be about a week out to allow you to tell family and friends.
3. Equipment changed (seat purchased).
This also happens and if there were any major changes that affect you (for example, you could no longer hold business class or the reduction in size was such you were going to be bumped), you'd be notified, most times by e-mail. A minor change from, say 50A to 30A would be handled at the gate.
The reason for handling seat assignment changes at the gate is that not every passenger selects their seat, so it is far easier for the gate agent to begin moving people around than having the computer system to it weeks in advance.