IME, an easy update or .bomb projection the night before a flight means little when a delay occurs.

Departure time is almost always revised, usually due to an aircraft substitution.

My home airport is BUR and one thing I love about flying out of BUR is that I have a direct number to UA (now Skywest ) where I can call and get precise information about delays. I run into flow control issues from time to time flying up to SFO and calling BUR will often yield more accurate information than checking on .bomb or calling HAL.

Next time, you might try calling BWI and ask to be transferred to UA.