Asking for capacity

Hi Miro Team,

We are design community from Myanmar and planning to host an online webinar (which will be recurring once a year) on next month. For the networking session. I would like to use Miro as a whiteboard where the designers can view and edit.

Current registered amount is around 400 and I am thinking whether it is possible to do it in the Free Plan? (I know paid plans will be better, but we are on our start phase and don’t have much budget at the moment.)

Or if it is not available or feasible in the free plan, please suggest me the package that is suitable.