How to activate T-Mobile's free Apple TV+ subscription?

According to T mobile I can take advantage of the 6 month free Apple TV+ subscription. It will automatically pause my own 1 year paid subscription and resume once the 6 months is over. Has anyone encountered this? I am concerned that once resumed I will lose some months. This is a new policy. In the past if you already had a subscription you could it take advantage free offer.

[Re-Titled by Moderator]

Original Title: T mobile free subscription to Apple +