In the EASA Part-66 regulation is stated that only after 90 days you can retake a specific Part-66 Module Examination. Only after a dedicated re-training by a Part-147 Maintenance Training Organisation you are entitled to retake an examintion after 30 days. The maximum number of retakes is 3 consecutives attempts, after the third attempt you must wait for at least 1 year. This is regardless if these examinations were taken at other approved Part-147 Maintenance Training Organisations.