So, series 3 is a single episode
Thanks to the allegations against Neil Gaiman, we might at some point get one 90 minute finale to the show, and not a 3rd series as such. If we get anything at all.
I certainly hope there's no truth to the claims, as I adore Gaiman's writing. Unfortunately Gaiman already responded to the claim by writer Julia Hobsbawm that he misread the situation*, so that doesn't bode well at all.
*https://www.tortoisemedia.com/2024/08/01/exclusive-two-more-women-accuse-neil-gaiman-of-sexual-assault-and-abuse/