Hi All,
I had lost the "Schedule Service" option a couple of weeks ago...
It is now back.
Tesla did many software and database upgrades in the past few weeks for the Summon and other things.
You might want to check the version of the app. to be sure: Currently mine is 3.10.0 (acd88ae81) on iPhone.
There were also times during the upgrade where I could not access the car(s) and also
trying to sign into the app gave a "Sign-in Failed" - "The email or password you entered was incorrect."
The email and password were correct and after several hours it accepted the Sign-in...
Keep trying,
Shawn