Regardless of the room you have chosen, whether it is for webinars, groups or one-on-one, the start time you set is the one that will enable or turn on the room, which is enabled about 15-20 minutes before the start time.
If the room detects inactivity from the time it is turned on/enabled for 30 minutes, it will be deactivated, in which case you must:
1. modify it to a future time
2. or create a new training
3. contact [email protected] to have it activated manually
The end time, however, is informative since the virtual room is not deactivated at the time you have set, but rather it is deactivated when the last person leaves.