After upgrading a site and all plugins, we found that TEC was hijacking a child page of the Events page. The child page is a posts listing page and was called Past Projects (slug: past-projects). Attempting to display the page, the content showed a title of Past Events and a Next Event button. (there were no past events)
Changing the parent from Events to another page everything worked correctly.
Our work around was to change the page slug to old-projects and leave the title as Past Projects after which it worked correctly as a child of the Events page. Further playing around showed that any child page with past in the slug was hijacked.
If TEC is going to hijack a page, it should be part of the settings and use a complete page slug rather than a fragment.