Architect Flow Timeout on High Concurrency Agent Script

Is it possible to configure a custom timeout for script-handler-v2 calls when handling 500+ concurrent sessions?

Ran JMeter test with 500 concurrent sessions hitting Architect flow script-handler-v2. Flow uses Wait action for 30s then Play prompt. Under load, 60% of requests fail with 408 Request Timeout. The default 30s seems too short for queueing delays. Increasing JMeter ramp time did not help. Need to know if Genesys Cloud allows extending this limit or if we must restructure the flow to avoid long waits under heavy load.