Infinite (inf) values in cumulative feeds

I have a cumulative kWh feed which has massively large numbers in it. These show as “inf” if I download the data, and break the graph viewer (ie. doesn’t load unless you set it before the first inf value, on 12/09/2018 0:31). On the interface it shows -5.2192851139879e+176.

The cause of these is probably posting with problematic IotaWatt (now fixed). There are several feeds like this.

I’ve seen others ask about “fixing” feeds, but there appears no good method. Is this still the case? If so, is it feasible to fix via (1) repeated use of api:update or (2) download, delete poor values, upload via api:insert? Is there another better method to ‘repair’ cumulative feeds?

Thanks in advance, Brett