No, you can't defer your dissertation deadline to next year. However, if you are suffering from health issues, you may defer it. Also, you need to submit a medical report. But most students want to defer the dissertation due to not being sure about the research question, not having methodology, lack of reading and slow data entry. Due to this, students get anxiety and depression because, without a dissertation, you can't complete your degree. So most students get masters dissertation help for topic selection, proofreading, literature review and complete dissertation writing. In return, they get good grades and enjoy work and studies.