Adding metadata to document page chunks

With ByAldi doing indexing/retrieval on the page level by default, I wanted to extract data (e.g: {List[Question: Answer], Title}) from each page and add that to the page metadata and back to the collection for improved retrieval and tracking.
The problem is I cannot figure out how to access the collection of pages of my documents, add data to those pages and save to disk.
Is that even possible with the early state of ByAldi?