If I choose to Upgrade my Internet Will it take effect that day?

[news]

[wireless]

I'm intrested in upgrading soon, but I'm curious..

-Will doing so shut my internet off until the upgrade takes effect?
-Am I charged Right away or on my next Bill?
-Will me upgrading take effect right away after payment?

I can't find much info going threw the steps and I just don't want to do it today only for it not to be working till the weekdays.

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