I'm a Postpaid subscriber. I don't understand what you mean by "1 GB a day or 3 GB per month (whichever comes first)".
Your internet speed will slow down when you use up 1GB of data for the day, or have accumulated 3GB of data usage for the month.
Once you hit the 1GB/day threshold, you'll be throttled to a slower speed, but no worries because you can still surf! You'll move up to normal speed at midnight. If you hit the 3GB/month threshold, your speed will move up to normal speed on the first day of the next calendar month.
To make the 3GB/month threshold clearer, here's an example:
You use 250MB on Jan. 1, 300MB on Jan. 5, 200MB on Jan. 10, 440 MB on Jan. 14, 1GB on Jan. 15, 300 MB on Jan. 21, 250 MB on Jan. 25, and 308 MB on Jan. 29. On Jan. 29, your internet service will slow down for the remaining days of January.
Just remember, it's a cumulative threshold. This means your data usage adds up.
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