You inquire about JAA/EU...
I did such training for DEC on 747 with Air Atlanta in 2004... Bournemouth.
Initial training was to "proficiency" - did not specify minimum hours required.
We did 3 training sessions and 1 check-ride.
The F/O had never been in a 747. He failed his check.
Most airlines may have specified hours for new crewmembers on type.
Recurrent training is generally 1 training session (2 hrs), then 1 check-ride.
xxx
Happy contrails