Feel free to ask questions about the jam here..!
The theme will be announced on the main overview page here on itch.io on the day the jam starts. And also in our Discord server (link is also on the main overview page: https://itch.io/jam/goedware-game-jam-4)
I think it will be easier to use the itch.io devlog feature that is included on their website. When you add the game for the game jam, you can also easily add a devlog. See this topic how-to: https://itch.io/jam/goedware-game-jam-4/topic/1877228/how-to-add-a-developer-log...
And you can already add a devlog when the game is not finished yet.