Hi Jason,
The BigBlueButton server does not remember anything between presentations. This means the server does not support persistent rooms or ability to upload content for a session that starts at a later time.
The reason for this approach is it makes the server stateless and much easier to create. Think of it like a web server: you don't have to tell your web server that you will be accessing a document tomorrow at 1PM. You just access it and the server responds.
It's similar with BigBlueButton. There is no user database in BigBlueButton, no pending requests database, no pre-uploaded slides database -- if fact there is no persistent database at all.
Regards,... Fred