They log in with their Webex account at https://uni-ulm.webex.com (or go to "schedule" in the desktop app "webex meeting" ) and schedule the corresponding meeting there. They also invite a few people, at least their boss. AFTER that you can see a list of upcoming meetings in the "Home" or "Meetings" section. Select the appropriate meeting. Then you will see information about this meeting, including a list of invited participants on the right side. To the right of the name of your boss you will see three dots. Click on them and select "Assign alternative host". Then your boss, independent of you, can start the meeting and host it.
Of course you can do this not only for the boss, but also for colleagues. In any case, the "alternative host" also needs a Webex account, while the other participants do not need one.
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