Do you switch to data roaming to use the $10/day international data program? And when you switch to roam on a US based unlimited plan you then get unlimited data in a country such as Kong Kong? Cirrrct??
When roaming internationally, you must have data roaming enabled to use data regardless of what plan you have. With the $10/day plan, turning data roaming on/off is actually a way to control whether you get charged each day. As long as you are in a supported country, yes you get unlimited data if you have the unlimited data plan.
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