We have a 30 day grace period to allow for plenty of time to sort out any payment failures. In the event this grace period expires, we would have a conversation with you. You never need to worry about an unexpected interruption of your service.
Your users will continue to receive the correct variations for their flags. The only impact is that once your payment is more than 30 days late, you will hit a paywall when trying to log into your LaunchDarkly account.
Contact support@launchdarkly.com if you have any concerns or require any additional support or information regarding a payment failure.