Q: Will they self assign to a default? A: No.  Tickets that already exist will not re-assign themselves to a default Help Topic if you remove an existing one.  However, you can always just mark the old Help Topic as "Disabled".  This should let you limit the number of the Help Topics moving forward (by having historical ones that are no longer usable).  If you want to move them to another Help Topic all together (there is no way to massively do this in the ui currently, but you can do it one ticket at a time see after the example below) but you could write some MySQL queries to update them for you.Example:If you look at ost_help_topicYou might  see that Computer Support is topic_id 1, and Computer Support / Password Change is topic_id 9.Then you could write a mysql query like:UPDATE ost_ticket SET dept_id='9' WHERE dept_id='1';Which should have the result of changing every ticket that has a "Computer Support / Password Change" (#9) to "Computer Support" (#1).  End Example.You can do that for each change that you want to make.  Alternatively you can edit each ticket, and change its help topic.  Depending on how many tickets you have though the SQL route is probably the way you want to do it.