47 CFR §90.135

1. (a)In addition to those changes listed in § 1.929(k) of this chapter and in accordance with § 1.947 of this chapter the following modifications may be made to an existing authorization without prior Commission approval:
   1. (1)Change in the number and location of station control points or of control stations operating below 470 or above 800 MHz meeting the requirements of § 90.119(b).
   2. (2)Change in the number of mobile units operated by Radiolocation Service licensees.
2. (b)Unless specifically exempted in § 90.175, licensees must submit a Form 601 application for modification to the applicable frequency coordinator for any change listed in § 1.929(c)(4) of this chapter.