If you wish to do your Master's Thesis Project across three semesters, you should consider if you are well equipped to start working on the project one semester earlier than usual.
Moreover, you should comply with the active enrolment requirements and the maximum duration of study.
Administratively, a Master's Thesis Project done across three semester can only be registered with 20 ECTS per semester. To ensure that the thesis is the concluding examination, it must be the sole enrolment in the 4th semester.
Consequently, you must pass a total of 30 ECTS besides the thesis project in the 2nd and 3rd semesters, that it 70 ECTS overall. The exact distribution of the workload is to be planned in consultation with your thesis supervisor or a student counsellor.
The intended actual workload is a total of 30 ECTS per semester.