The Conferderation of European Baseball released an umpire list for the upcoming 2015 season. There are 5 categories of umpires: AAA, AA, A, N and new umpires. You may download the complete list here.
When you get the rank?
AAA experience in CEB events for at least two years and an average uc points
AA experience in CEB events for at least two years and an average uc points
A nominated (new) international umpires
The events you can be invited:
AAA all CEB events
AA all CEB events exclusive Euro Cup, Final 4 and European Championships Seniors
A all CEB events exclusive Euro Cup, Final 4 and European Championships Seniors
The list contains 124 umpires in total: 17 AAA, 24 AA, 48 A, 23 N and 12 new ones.