User disconnection time may be influenced by many things.
- If the user was involved within a transaction it may be necessary to undo work which had been initiated but not completed by the user.
- If a large amount of data had been changed more time may be required to undo the work.
This might require varying amounts of disk I/O to undo changes made to the database.
- Disk resources may be a factor.
- CPU resources may be a factor.
If work must be undone, the user will still appear in various menus within PROMON or the Virtual System Tables (VST's).
The user will likely no longer be listed in the disconnection lists since a flag is set once the disconnect command is initiated which will remove the user from the menus where disconnecting is an option.
For further investigative Steps, refer to Article Client session hangs, but user is still showing in user control table within Promon 
