A methodology includes servicing a voice call between mobile User Equipment and an Enterprise Session Initiation Protocol (SIP) Services Environment using, at least in part, Voice over Internet Protocol Multimedia Subsystem (VoIMS), detecting that the User Equipment is moving out of range of Radio Access Point (RAP) infrastructure servicing the User Equipment, and in response to detecting, initiating a procedure to hand out the voice call and anchor the voice call in a Mobile Switching Center (MSC) of a macro service provider.