Endpoint Encryption

I can reboot through Remote Desktop using "shudown /r" DOS command.
However, the PC will not reappear visible to Remote Desktop from my remote location.
This makes sense since, EnPoint Encryption won't let Windows Start until somebody type the EE password.

A Symantec solution could be to offer a special reboot function.
This EE reboot would ask for EE password and use it automatically while rebooting.

Am I missing something ?

There isn't a command / client method but there is a policy option - have a check in the documentation about AutoLogon. You can set the computer to autologon x times until a certain time for this kind of maintenance.

There is also a reboot utility what lets you restart once without the need of preboot auth. have a look at SEEReboot.exe.

About the Reboot Utility
The Reboot Utility provides administrators with the ability to bypass SEE Full Disk pre-boot authentication and restart a Client Computer remotely
 

Even better :-)