Fresh Kiro account → log in with Google / GitHub / Builder ID (NOT AWS IAM, kills the bonus) → hit https://app.kiro.dev/account/usage → smash Kiro Pro $20 → Stripe eats it with the $20 sign-up credit → Total: US$0.00 → drop card, subscribe, flip the model dropdown to Opus 4.7, go nuts.
Bonus is prorated by days left in month — upgrade Day 1-3 for full ~$20 off, late month = peanuts. Cancel before the 1st (Manage Plan) or auto-renew bites you for $20. One bonus per email, so burn it smart — fresh inbox for round two.
Stripe doing math wrong in your favor. Time it, cancel it, walk clean.
Thanks a lot @Ze380y it worked but it has some credit limits (Credits 0.64 used / 1000 covered in plan) and before starting prompting why its asking for GitHub access ?
Tried this way : Did convert the pro account to Free, then on 2nd June upgraded to Pro again. As per their Prorated Costs, the price was cut by half with a discount of some 12 USD. And for new accounts within the first week, there happens to be a small charge for taxes, other than this no other costs. Anyway it’s not a stripe bug. It’s Koro.dev internel mechanics seems to be messed up.
Kiro Pro = $0 First Month — Free Opus 4.7 Ride
Bonus is prorated by days left in month — upgrade Day 1-3 for full ~$20 off, late month = peanuts. Cancel before the 1st (Manage Plan) or auto-renew bites you for $20. One bonus per email, so burn it smart — fresh inbox for round two. 
but it has some credit limits (Credits 0.64 used / 1000 covered in plan) and before starting prompting why its 
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