I accessed the Centurylink website, and I found this material on data limit exceptions:
"CenturyLink Excessive Use Policy Frequently Asked Questions What is the CenturyLink Excessive Use Policy (EUP) and how does it apply to me?
CenturyLink residential High-Speed Internet (HSI) customers are subject to the CenturyLink EUP that
sets a 1.0 terabyte (TB) monthly limit on the amount of data a customer sends and receives over their HSI
connection, subject to certain exemptions.
What customers are excluded from the CenturyLink EUP?
CenturyLink’s EUP does not impact the following customers:
Business HSI Customers
Prism TV Customers
1 Gigabit customers
Customers with subsidized HSI service for low-income households
What is included in my usage?
All of the data received by your modem/gateway (downloaded) and sent from your modem/gateway
(uploaded) will be counted toward your data limit.
Why does CenturyLink have data usage limits and how much data usage is included in my
CenturyLink HSI service?
Data usage limits encourage reasonable use of your CenturyLink HSI service so that all customers can
receive the optimal Internet experience they have purchased with their service plan. CenturyLink includes
1.0 TB of data usage each month with all residential HSI plans."
If I interpret the above correctly, 1-gigabit (actually, 940 MBPS) customers are not affected by the 1.0 terabyte/month limit. I highlighted by coloring in RED the reference to "1 Gigabit customers", above.
But, it's possible that Centurylink's policies vary state by state, or region by region.
Jim Bell