Neon has the ability to make a Copy-on-write replica of a database, which for you would allow you to create an instant read-only copy of the data that has been

Neon has the ability to make a Copy-on-write replica of a database, which for you would allow you to create an instant read-only copy of the data that has been ingested up to that point, without significant storage overhead. The new data would still be written to the primary database, and long running queries would only see the snapshot that the instance was started with (using their own pool of CPU and memory resources). Assuming that the extensions that you use are compatible (that is, they don't access database files in a way that PostgreSQL doesn't, and the licence is compatible) then Neon could be a good solution to that issue.