I have an SL1100, with 4 trunks.
lines 1 and 2 ring a virtual extension with a FWD on B/NA to an external number.
If the user has been talking on trunk 1 and wants to quickly answer trunk 2 they'd like to just press the line key for it. However, when pressed they get an error tone.

I'm thinking there must be a class of service setting to allow the user to answer the trunk, but i have no idea what it is.

A little help would be awesome. Thanks