When I hit my limit, I add back more credits, which updates the webpage yet I still have all requests routed to the slow queue for 10+ mins afterwards.
Updating your allowance on cursor.com should work almost instantly!
You may find better traction with our usage-based pricing feature, as with that, you only pay for what you use. A premium request is currently $0.04 for anything over your limit, and you can set a maximum amount before it moves to slow requests again, if that is helpful.