Most of document erased after iOS 18 update

I use Pages on an iPad and Mac. A document that I’ve been adding to since January 2024, almost daily, I went to add to it and most of the document is gone, months of work, poof.

I use iCloud. I don’t understand how an update could/would remove parts of a document that has been regularly been updated and kept on iCloud.

My Recent folder is also a mess, it shows a jumble documents I haven’t touch in years or months as being recently accessed, nothing that I’ve actually worked on recently is visible.

I’ve never had documents altered after an update though, this is a first.

Is there any way to recover? Unfortunately I was mostly using my iPad for this particular document, I have Time Machine set up on the Mac.