when the last new drop was added, the drop was 1 chance per day.
the old mount was considered “legacy” and would still drop at its original rate
The place where blizzard sends us to obtain infomation, stated the same thing.
New Mount, Ensembles and Toys - Brewfest 2025 Updates - Wowhead News
We were told that this works the same way, and have now missed out on a heap of chances to get it.
(not that it makes a scrap of difference to me, it wouldn’t drop for me anyway, and it’s ugly, so not going to do anything beyond the “singular increased chance per day” attempt)