No – it requires admin level permissions to be able to edit the after message destination since the destination can (and often does) include external directory objects and system level conversations that users do not have rights to see (i.e. going to the say goodbye call handler is typical) – user level permissions do not get to look at call handlers, interviewers, name lookup handlers and such, and so would not be able to set it back.
The typical way to handle this is if the site is using alternate greetings for holiday purposes as a rule the admin can bulk change the after greeting action for alternate greetings to be hang up (or more likely to go to the say goodbye call handler which is a little less rude) and when users activate their alternate greeting that’s the behavior. This can also be set in the user templates, of course, so that all future users created have this behavior.
There’s no way to have users leverage the alternate greeting for taking messages and then later for not taking messages and back again without admin rights.
