As others have noted, there's an additional $30 processing fee for transfers. So 20K miles actually costs $230 to transfer and is probably not worth it (given that 20K miles is only worth about $200 - $230).
Also as noted, there are different award levels for roundtrip vs. one-way awards on most EU awards and that is also the case here. There are also different levels depending on day of week. The cheapest one-way Main awards for CVG-EDI in March are 50K and require Sun-Wed travel. Thu-Sat travel awards start at 54K one-way which is what you are seeing. The cheapest roundtrip awards on CVG-EDI in March in Main Cabin are 82K roundtrip and require a 7 day minimum stay and mid-week travel (Sun-Wed outbound, Tue-Fri Return). You might want to consider getting a DL Gold Amex for yourself and wife which is free for the first year and provides a 15% discount on Skymiles awards (if they are flown on Delta metal). 15% Amex discount potentially reduces one-way awards to 45.9K for Thu-Sat travel and 42.5K for Sun-Wed travel.




You can potentially get a roundtrip award for 69.6K miles roundtrip with Amex discount, but you'd need quite a bit of date flexibility for that.

A


These award levels (both the one-way and roundtrip levels) are blacked out for first couple weeks of April, but they are also valid for travel from April 17th - May 4th, 2025 (outbound).