Meetings to Webinar transition

Greetings,

My team will be organizing a webinar like event which is going to be involving around 500 participants. I went to the calendar and scheduled a webinar. We do not need the registration feature for this as this is considered an open event.

When I disabled the need for registration, it seems like just a regular meeting. I am scared at the day of the event, the link we gave out is only for Teams Meeting and will limit participants to only 250.

So my question is, will meetings automatically change to webinar when the participants exceeds 250? What should I do to make sure that this 500 participants will have access to the seminar we are organising?

Thanks.