when an extension is called directly, or a DDI reaches a specified extension, or a call is put through to an extension - the mobile/extension twinning should function. If that extension is a member of a group, and that group receives a call, we would like the ability to not have the mobile ring at the same time. e.g. a team of sales people who may or may not be in the office are all part of a sales ring group. If they're at their desk they should receive the sales ring group call, but if they're out of the office they shouldn't receive this call. Simplest solution is to not twin group calls.