There are several other benefits with delta (if you are platinum medallion or higher you can buy a coach seat and immediately upgrade to C+ for free ) and if the fares drop you just either rebook and get ecredit or call and have the agent do it to get the ecredit to apply to a future flight (within 12 mos of when the initial ticket was purchased). But these are more so Delta benefits than cr card benefits, though the cr card spend helps ti get higher loyalty status where more benefits kick in.
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