It looks t-mobile is making ipv6 a standard and not a oddball. You can define a APN with dual-protocol for your movil-device. T-mobile claims they have more ipv6 enabled clients than ipv4 which is good news if it's 100% true and can be validated.
My experience has let me to just enabling the protocol tab file with ipv4/ipv6 and disable the data systems and re-enable. In Samsung S5 mini, I had a ipv6 address pop up in a few seconds that's NOT ping able the following address was found under my ip status ( about device ) 2607:fb90:d77:ff9:0:46:2bdc:a801 for the south central Texas area.
The assignment that t-mobile uses;
You can follow past ipv6 news with t-mobile under the following link;
And my previous APN HOWTO blog post.
NSE ( network security expert) and Route/Switching Engineer
kfelix -----a----t---- socpuppets ---dot---com
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