Can we transform a Zoom meeting into a webinar without reprogramming the whole event?

I have been programming a meeting 2 weeks ago, that is evolving into a webinar, in one week time, and I was looking for an option to change a Meeting to a Webinar, as I saw this option exist: Changing a Webinar into a Zoom meeting with a  click of a button, but does the reversal is true ?  would be great !!!! 

The problem is that it will change the registration link !!! and people have already started registration under the meeting.

Many thanks,

Michel Reymond