Do I have to apply and do I have to meet deadlines?
For the doctoral procedure as such there is no selection process for a limited number of places. Nor are there deadlines. If you meet the prerequisites for admission as doctoral candidate and have found a supervisor for your doctoral project, you may apply for the admission as doctoral candidate at any given time.
If you wish to do a structured doctorate and complete the programme of one of the Graduate schools, however, you need apply for a place in the respective Graduate School as well, meet their criteria and observe their deadlines.