Apple notes that the encrypted messages are just a test and aren't available for all devices, carriers, or regions yet.

Once real-time location sharing is active in Google Messages, a persistent banner appears at the top of the chat, clearly indicating that live location sharing is on and showing how much time is left.

In the final window of the custom time wizard, verify the time and date, and then tap Save. Once you've done that, you'll see the text and time at the bottom of the window. Tap the Send button, and ...