/msg $C ADDTIMEDBAN <#channel> <mask|nick> <Duration> [Reason]
Adds an automatically expiring ban to the channel ban list. This command behaves in the exact same fashion as ADDBAN with the exception that the bans are automatically removed after the user-supplied duration. If it exactly matches an existing ban already in the list, the reason will be updated. If the existing ban was a timed ban, it will be extended. Timed bans can be removed with the DELBAN command, as with permanent bans.
$uSee Also:$u addban, bans, delban, durations