Is there a reason Delta waits to the very last second to post a delay?
 

6:25pm and plane to take us to HOU is still deplaning.
Delta app and board assured me the flight is on time for the 6:40pm departure.

Certainly not the first time this has happened and curious if there is some advantage for Delta to not post the obvious delay.

FA’s attended just arrived at 6:44pm but still on time:

6:52pm update. Just posted delay to 7:00pm departure.

Delta is actually better than most when it comes to this (although they are not perfect).

If you are not flying out of a hub (where plane swaps are more likely) just track the inbound flight.

I will cut them some slack as its the arrival time that really matters not the departure time and time can be made up in the air, in taxitime, faster boarding, better routing etc, so its still possible to arrive ontime even if departing after scheduled time. Additionally, once you post a delay, people don't show up until the new departure time, and if things are ready to go a few minutes ahead, its best to get people boarded so you can leave quickly. At the same time (and I know this is what you are getting at) DL takes forever to post delays even once it becomes mathematically impossible to have an on-time arrival. For those of us with short connections it would be nice if they could post the delays sooner, so we are eligible to change flights and not risk misconnects:mad:

Still at the gate and showing a 35 minute late arrival now.
The plane rolled up to the gate from an international destination n5 minutes to our departure time.

MAJOR EDIT TO THE BELOW ABOUT PROPS TO THE GA:
In the end was definitely still a YBYL. The two that came up from 10e and 12e were Delta FA's in unifrom. Two pilots (not DL - regional airline just can't remember which one) took the seats in 10e and 12e. After takeoff the app showed no one upgraded and row 2 unoccupied.

Props to the GA though. 2 no shows in row 2 and they moved up passengers from 10e and 12e and had the 2 non revs waiting for seats move to them.

in row 1 and got to hear it all.

Use flightaware.com. It is more timely and accurate than Delta. I've gotten info ahead of the SkyClub and gate agents on delays from flightaware. It will also show the incoming aircraft and you can go back several flights to see potential delays.

It also shows scheduled gate departure and wheels up scheduled time (and wheels down plus gate arrival) so you can expect a 40 minute trip from the gate to the end of the runway.

It's definitely not just Delta. United is just as bad and, IMHO, actually worse.

+1 on Flightaware.com, always has better info. Also tracking inbound will tell you a lot more than any board or GA.

Agree 100%, but be careful relying on it for large hubs. Delta is more aggressive on plane swaps than most other airlines. In Atlanta I've seen Delta do plane swaps to avoid as little as a 15-20 minute departure delay. If you are flying out of a non-hub they are highly unlikely to do a swap and it can be relied on without worry.

Pretty much all airlines do this. I've always assumed the philosophy is, the airline doesn't want people wandering too far away from the gate (or leaving for the airport later, if the delay is posted hours in advance) in case the delay ends up not being as bad as expected. Agree it can be very frustrating though.

As an FYI I do use Flightaware and it was showing no delay at the same times I posted above.

You have to track the inbound flight. If the inbound flight is not going to get to your gate until 9:30 AM and your flight is at 9:00 AM, you know it is going to be delayed. This does, of course, introduce the risk of a plane swap which I mentioned earlier.

That's what I was doing and how I knew there was no way we would be leaving on time despite the optimism of DL. ;)

I agree and I love Flightaware. For instance the first plane out in the AM from SJC to MSP arrives from MSP the evening before so its 99.9 percent on time or departs early from SJC unless its due to a mechanical issue.

I always track the inbound flight as more than likely its the one to operate the flight out to my destination unless you are at a hub and there is an equipment change at the last minute.

I love how Flghtaware shows how long the plane taxis to the gate and the constant updates like your flight just landed and is taxing to the gate. Its better than what the airlines can do for their FLIFO.