Hortsmann SIR-321: Sending Scheduling commands

I’m reading the SIR-321 Countdown Timer manual and I’m not sure if I understand it correctly because on page 17 they mention that the basic command class support scheduling through the "set"command.

Does it mean that I can send a “set 45” command to switch the SIR 321 on for 45 minutes instead of sending a ON command and running a separate timer to switch it off?