How can I control the reverse proxy timeout?

I'm using a reverse proxy to access my backend. Some of the requests are running a bit long (more than 30 seconds). When this happens, I end up with a 502 because amplify isn't allowing the backend to take that long. How can I configure this. Not seeing anything in the UI or the docs.

No file, test, or entry point is mentioned. Start by checking the AWS Amplify Hosting documentation and configuration options for reverse-proxy and backend timeouts; done means identifying whether the 30-second limit is configurable and documenting the supported setting or limitation.

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