group ZOOM

Welcome to the Zoom Community, @Tomcat.

Check out these Zoom Support articles on Join Before Host and Starting a Meeting Without the Host. Set up a meeting with the settings indicated, and anyone can join any time.
https://support.zoom.com/hc/en/article?id=zm_kb&sysparm_article=KB0060501 

https://support.zoom.com/hc/en/article?id=zm_kb&sysparm_article=KB0058759 

Note that the meeting duration limit for Basic accounts still applies: meetings are limited to 40 minutes, and a 10 minute waiting period is required before a new meeting can be started. 

https://support.zoom.com/hc/en/article?id=zm_kb&sysparm_article=KB0067966