Teams webinar poll participant numbers

I'm trying to work out whether a Teams webinar using a premium account will allow more than 300 people to take part in a poll. At a recent webinar with over 500 attendees the polls crashed because too many people were trying to vote.

According to some info I'm finding online, a webinar set up with a premium account will enable 1000 people to take part in the poll. However, other places seem to suggest that still capped at 300.

Anyone know for sure?