A dynamic queue is created upon authentication of the PPPoE session. Dynamic entries can never be changed, only removed.
It would be nice if UM could kick a user when rates are modified from the UM GUI. Perhaps another button which says SAVE AND KICK instead of only SAVE on the UM GUI.
I normally kick the user manually when I changed rate settings.
That would be possible, if User Manager supported RADIUS incoming messages. But currently it is not supported, as far as I know there are plans to add support for such feature in the new User Manager.