From Elendor
The +COMSET system allows users to define "sets" of channels which they may
"switch in". When you "switch in" a channel set, you automatically leave
all channels that you are currently joined to and which are not in the
channel set and you automatically join all channels which you are not
joined to and which are in the channel set. Help is available on the
following subtopics:
See HELP +comset define for defining new channel sets.
See HELP +comset add for adding a channel to an existing channel set.
See HELP +comset remove for removing a channel from an existing set.
See HELP +comset noleave for how to avoid leaving your existing channels.
See HELP +comset list to list your channel sets and their contents.
See HELP +comset default for specifying default channels in channel sets.
Once you have a channel set, you may switch it in with the following command:
+COMSET <name of channel set>