Hey Shane,
Unfortunately, that is not a unique situation and Quickbase has hard upper limits on some storage, so we are unable to "buy more horsepower." However, file attachments may be different, in that perhaps you can purchase more space? I'd open a Quickbase Support Ticket or review your contract (or Billing in the QB Admin Console) to confirm.
In addition to what Mark suggested using Juiced Tech (which we've used with success in the past and would recommend), we also leveraged Pipelines to create Google Drive links to records and store files in Drive folders too, instead of native Quickbase.
The place you're stuck now is migrating the existing file attachments from Quickbase to some third party, like AWS or Google, and ideally users wouldn't have to look in an archive prior to certain date. In other words, it may be nice to keep their workflow the same regardless of project age … Juiced should be able to help with the "sweep" functionality I imagine, otherwise you'd find a developer who can write a script to migrate your data.
Also, to buy more time until you find a solution, I suggest checking the field properties of each of your three fields in Table "A." Scroll down to the "File Attachment field options" and review the value set in the "Keep the last (revisions)" which defaults to 3. If you don't need older versions, you may be able to set this to 1 and free up some space?
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Brian Seymour
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