Managing exported content

When using an online Satellite to sync and export content for later importing to an offline Satellite system, what is the requirement for retaining the exported content on the online upstream server?

These exported (and chunked) repos are pretty big and over time additional incremental exports contribute to increased disk consumption. Is it safe to remove these once imported downstream, or do they need to be retained for future incremental exports?

Short of adding more disks, eventually I'll hit a capacity limit and need to start discarding things.

How do others manage this burden?

EDIT:
For clarity, the base exports are complete, followed by several incremental's.