Well, I've got an answer from Cube. A bit late, took them 11 days, but better later than never.
The Attention has 29er wheels, so the ERD is 622mm.
In the two smallest sizes, it has 27,5 inch wheels, so the ERD here is 584mm.
We hope we were able to help you in this matter.
So maybe someone will search for this information about Cube Attention. Maybe it will be useful for someone.