What is Release Privilege?
When you have succesfully passed all the EASA Part-66 module examinations you must first gain a couple of years of Experience. Then you can apply (at the NAA of an EU member state) for an EASA Part-66 Aircraft Maintenance Licence. Then you need to follow a specific Aircraft Type (or Task) training, for example “Boeing 737-600/700/800/900 (CFM56)”. To add the first aircraft type to a Part-66 (Cat B1 or B2 rating) you must succesfully complete the: Theoretical element + Practical element + On-The-Job Training.
Then the approved maintenance company, being a Part-145 (Or Part-M supart F) can grant you the “Release Priviledge”. With this priviledge you are allowed to release aircraft for service on behalf of the Approved Maintenance Company.