Section 101.1331 - Treatment of incumbents(a) Any MAS station licensed by the Commission prior to July 1, 1999 in the 928.0-928.85 MHz/952.0-952.85 MHz/956.25-956.45 MHz and 928.85-929.0 MHz/959.85-960.0 MHz bands, as well as assignments or transfers of such stations approved by the Commission and consummated as of January 19, 2000, shall be considered incumbent.(b) Incumbent operators in the 928.0-928.85 MHz/952.0-952.85 MHz/956.25-956.45 MHz bands are grandfathered as of January 19, 2000, and may continue to operate and expand their systems pursuant to the interference protection and co-channel spacing criteria contained in § 101.105 . (1) MAS operators are prohibited from acquiring additional frequencies in the 928.0-928.85 MHz/952.0-952.85 MHz/956.25-956.45 MHz bands and the 932.25625-932.49375 MHz/941.25625-941.49375 MHz bands for the purpose of expanding private carrier service and from changing the use of their frequencies in any manner that is inconsistent with this part. Refer to § 101.147 for designated uses.(2) Incumbent operators in the 928.0-928.85 MHz/952.0-952.85 MHz/956.25-956.45 MHz bands will include incumbents as defined in § 101.1331(a) , as well as, their transferees and/or assignees and the successors of the transferees and/or assignees and retain their grandfathered status, provided that the use of the MAS frequencies remains unchanged from that of the transferor and/or assignor of the license.(c) Incumbent operators in the 928.85-929.0/959.85-960.0 MHz bands are grandfathered as of January 19, 2000, and may expand their systems provided that the signal level of the additional transmitter(s) does not increase the composite contour that occurs at a 40.2 kilometer (25-mile) radius from the center of each master station transmitter site. Incumbent operators and geographic area licensees may negotiate alternative criteria.(d) The frequencies associated with incumbent authorizations in the 928/959 MHz bands that have cancelled automatically or otherwise been recovered by the Commission will automatically revert to the applicable EA licensee.(e) The frequencies associated with incumbent authorizations in the 928/952/956 MHz bands that have cancelled automatically will revert to the Commission.65 FR 17450, Apr. 3, 2000, as amended at 66 FR 35111, July 3, 2001