47 CFR § 22.705
Rural radiotelephone system configuration
February 16, 2021
Stations in the Rural Radiotelephone Service are authorized to communicate as follows:
(a) Rural subscriber stations are authorized to communicate with and through the central office station(s) with which they are associated. However, where the establishment of a central office station in this service is not feasible, rural subscriber stations may be authorized to communicate with and through a base station in the Paging and Radiotelephone Service.
(b) Central office stations may communicate only with rural subscriber stations.
(c) Interoffice stations may communicate only with other interoffice stations.