Your thesis should be submitted after you complete the minimum period of study and before the end of the maximum period of study for your qualification.
For full details on minimum and maximum periods of study, please see University Regulation 6.2.3.
You are advised to discuss when you intend to submit with your supervisor, but please remember that their advice and/or opinion are advisory only. The decision when submit to thesis is yours and the advice from your supervisor should not be taken as an indication that the final thesis will necessarily meet the requirements of the degree.
Exceptionally you may be granted permission to submit your thesis before the end of your minimum period of study. For further details see to the Early submission webpage.