Courses will enter a read-only state within a few weeks after the semester ends. Students will be able to view course content after this point, but will be unable to interact with the course site. (See also: How do I find a past Canvas site?)
Likewise, instructors and course admins will lose the ability to edit their course site after this point. The site will remain available in a read-only state and all course content will be accessible and downloadable by class staff, but no further changes or additions can be made.
Class staff may extend or shorten the time a course remains open in advance. If you wish to set a later end date, make a course site read-only sooner, or restrict student access entirely after the term ends (rather than allowing read-only access), these can be configured via the Settings page.
We highly recommend setting an appropriate end date in advance if you want your Canvas site to remain open beyond the end of the term.
More information on configuring this setting is available from Canvas here.
If your site has closed and you need to make a change to it, please contact firstname.lastname@example.org.