Registration and no fixed time

Thank you for your response. I don't remember seeing any warnings. What a disappointment, there should be some option to this.
Regards

it is quite disappointing , I lost data of about 300 attendees on my webinar. I think I will have to send them invites and approve again manually 

The relevant question for me is why is there no registration option for the "no fixed time" option?

I have a seminar series for which I need participants to register. I need them to register, but there is no regular date. They are roughly monthly, but the dates are going to change from month to month. I created a short URL for the registration page that I want to put on all my publicity materials. For now I just created 1 occurrence for the first one this year. But I cannot add additional dates unless they are exactly one month apart.  I think I'll be able to edit the past meeting once it's over and set it to the date of the next meeting. But this won't allow me to let people register for the next several meetings all at once. This is a real problem. Why can't I give it a list of dates and times for a recurring meeting? 

It is still the case where if you change from a scheduled time to 'no fixed time' you lose all your registrants and there is still no warning that this is going to happen. The pop-up screen is about notifying your registrants about the change. Nothing about how you'll lose them.  I've lost of 1300 registrants, because we were unsure about the next date and 'no fixed time' would be an obvious way to put a pause on the schedule and still allow people to register. 

I've seen the warning they suggest we should see, but it doesn't happen with this particular set of operations like support seems to believe.