Migrate Site to Heroku or other hosts

My Ruby-powered back end and React front end are running on AWS right now, but the monthly bill has grown too high. I’d like the entire application moved to Heroku while keeping every feature—Stripe payments, user auth, e-mail notifications, and the Webflow-hosted landing page—working exactly as they do today.

You will:
• Spin up a new Heroku app, choose the correct Ruby and Node buildpacks, and configure deployment from my repo.
• Re-create and migrate the production database.
• Transfer all existing environment variables and secrets so Stripe, e-mail, and any third-party APIs keep functioning.
• Point the Webflow landing page to the new Heroku endpoint and verify front-end assets load properly.
• Run a staging deployment first, run through checkout flows with me, then promote to production with minimal downtime.

Please confirm your approach to handling environment variables on Heroku, give an estimated timeframe, and share any similar migrations you’ve completed.