Originally Posted by
ATOBTTR
The one caveat is sometimes DL makes it difficult to rebook the same flight in the same cabin so you either have to call and have an agent do it or rebook to a different cabin or different flight and rebook back to your original flight and cabin, hoping that in the couple minutes it takes to do that, the fare you are truly rebooking to doesn't disappear.
Good to know!
With award ticket i made a double booking, then cancelled the first one. For e-credit that's not a good strategy of course