The Broadband Resiliency and Flexible Investment Act aims to accelerate the deployment and modification of telecommunications infrastructure by amending the Middle Class Tax Relief and Job Creation Act of 2012. It mandates that state and local governments must approve eligible requests for modifications to existing wireless towers, base stations, eligible support structures, and telecommunications service facilities. This approval is required if the proposed modifications do not substantially change the physical dimensions of the existing infrastructure. A key provision introduces a 60-day "deemed approved" timeframe, meaning if a government fails to approve or determine a request ineligible within this period, the request is automatically granted. The bill also establishes clear rules for tolling this timeframe, primarily for incomplete submissions, requiring specific written notices that identify missing information and cite publicly available rules. Furthermore, it explicitly prohibits state and local governments from requiring pre-application steps or documentation not reasonably related to eligibility and not specified in public regulations. To ensure compliance, the legislation allows requesting parties to bring actions in U.S. district courts, which are mandated to provide expedited review . The bill also defines what constitutes an "eligible facilities request," including modifications for collocation, removal, replacement, or improvements that enhance resiliency and provide a direct benefit to public safety , such as backup power or hardening. The Federal Communications Commission is directed to issue implementing rules within 180 days of the Act's enactment.