What we don't know - at least, I certainly don't know, and I've not seen it described here, ever - is what exactly the processing path of that data is after our raw results are returned to the server.

We do know that each of our tasks forms part of a sequential sequence of (currently) 10 tasks making up the entire job, and that at least some of our returned data is used to assemble the starting data for the next task in the sequence.

Is it all used in that way? Once it's been used, does it need to be kept? If so, how long? Can it (any of it) be discarded once the next task in sequence has been created? Has been completed? Once the whole 10-task job has been completed?

People in other threads have mentioned SETI as a comparison. There, the process is that the scientific data returned by each task is assimilated into a gigantic, 20-year, scientific database. And that once assimilation has taken place, our raw, returned, data is erased (usually within 24 hours).

If we knew for certain that our returned data needed to be retained in quick-access online storage, say until the final paper had been accepted for publication following peer review, then I'd be prepared to contribute to a fundraising drive for additional disk spindles and a chassis to mount them in. But if the daily data is simply transferred over a slow link to an offsite backing store, then spindles aren't the answer: more drives would simply delay the need for an outage from a 5 day to a 10 day interval, and then extend that outage when it eventually arrived.