Then how does the new "miles per dollar" method of determining RDMS enter into the accrual of MM's? For example, on a recent booking, I'm flying 5,278 miles, but only receiving 2,456 redeemable miles based on the GM multiple times the base fare.

Will the MM's follow the exact miles flown, the rounded up miles flown for trips less than 500 miles, the MQM's bestowed, or the RDMs calculated from the fare price?


Unfortunately, mine did. And I'm not sure why. And, I could be wrong. However, about 5 years ago, I printed out my entire activity of over 50 flights spanning two years when I noticed the drop in MMs after an award redemption.

It was my intent to analyze each flight line by line to audit the miles change, but that is like planning to clean the empire state building with a toothbrush... a task repeatedly postponed due to the low priority tedium requiring more time than duly commensurate with any possible benefit, given the improbability of Delta making a change, especially the longer I procrastinated the undertaking.

So, it was my hope that if the deduction of MM's was commonplace, people here would know about it, and the logic could be explained. But it sounds like MM's are not supposed to deplete, so my situation appears to be anomalous, or more likely misunderstood by me.