With what frequency does the AWS API Gateway assign a new IP address?

IP assignment is not tied to session state - the mapping is driven by the unique source IP of the incoming request, not by the establishment or teardown of a session.

AWS API Gateway does not rotate IPs on a per-second time interval; the IP presented to the destination is determined by the incoming request's source IP, not a time-based mechanism.

A new IP is not guaranteed for every individual request - repeated requests from the same source IP will present the same outbound IP; the rotation occurs across different unique source IPs.

AWS API Gateway routes requests through AWS infrastructure and presents a distinct AWS-owned IP address to the destination server for each unique source IP that sends traffic through the gateway. This per-unique-source-IP behavior means a target sees different IPs depending on who is making the request, which is commonly exploited to bypass IP-based rate limiting and access controls.