I experienced twice that I closed support ticket but after week someone replied to it. I found this after another week. Would be great if closed tickets reopen when new content appears.
When user reply to closed ticket, UserEcho set Needs review state to is. So all tickets, where agent/admin action is required marked as Needs review. It's default filter in our agent interface.
More explanation and helpdesk best practices here. http://feedback.userecho.com/topics/7878-filtr-trebuyut-vnimaniya-zachem-on-mne-nuzhen/
Please reply is it helpful for you?