Proceed as follows:

Incoming calls must be put manually into the waiting field.

Incoming calls are automatically put into the waiting field if all waiting field reception phones are busy. (In this case, “busy” means that there is an ongoing call in the active waiting field receptions or an outgoing or incoming call is ringing. If a caller is waiting in the waiting field, this does not count as “busy”.)

After 0..120 sec.

Incoming calls are indicated for a duration of x seconds in the waiting field reception and then automatically put into the waiting field if not already accepted manually.

Select the group that is to be used as waiting field (alternatively single waiting field reception).