Great news! I just got off the phone with tech support and have learned that we don't require the old "station lock" feature on the SBX. If a phone & DSS combo get swapped, they just don't work. The jack knows that it is supposed to be either a phone linked to a DSS or a DSS linked to a phone. AND, if a 24 button and an 8-button phone get swapped, the system remembers the original phone's settings and they are preserved. So, as a useful example, if an 8-button phone is used and activating a particular feature is more easily done from a 24-button phone, just plug in the 24-button phone, activate the feature, then return the 8-button phone to service. Voila! (That's for any French Canadians!)