Ever hear "If you know the extension of the party you are trying to reach please enter it now."? Unfortunately, an extension standard does not seem to exist at

Ever hear "If you know the extension of the party you are trying to reach please enter it now."? Unfortunately, an extension standard does not seem to exist at the carrier level? But, NAT is also private. Some CMS likely has the ability to auto route a callback to the same extension/agent given his or her current status without requiring entering an extension.