How do I know when T-mobile makes changes to the contract?

Their “consume code” states that

7. Provide customers the right to terminate service for changes to contract terms.

“Carriers will not modify the material terms of their subscribers’ contracts in a manner that is materially adverse to subscribers without providing a reasonable advance notice of a proposed modification and allowing subscribers a time period of not less than 14 days to cancel their contracts with no early termination fee.”

But I can’t figure out how I’m supposed to know when the contract has been changed or not?

The website is www.t-mobile.com, (surprise surprise) and here’s a link to the “consumer code” if you want to check it out too.