At least one new carrier is coming for 2017.
Someone on airliners Boston thread was on Google flights and noticed Air Europa, a fellow Skyteam partner of Delta's, had loaded Madrid-Boston flights starting June 12.
The schedule is Sun/Mon/Wed/Fri
UX31 MAD-BOS 3:30pm-5:20pm
UX32 BOS-MAD 10:50pm-11:40am
Air Europa's site is showing a later depature 11:40PM
Someone on airliners Boston thread was on Google flights and noticed Air Europa, a fellow Skyteam partner of Delta's, had loaded Madrid-Boston flights starting June 12.
The schedule is Sun/Mon/Wed/Fri
UX31 MAD-BOS 3:30pm-5:20pm
UX32 BOS-MAD 10:50pm-11:40am
Air Europa's site is showing a later depature 11:40PM