I found out that Tardigrade is represented by something else in the Duplicati dropdown list now, so your article could do with being updated.
I could not use Tardigrade in the end, as the only card I can offer for payment is reported as a “Prepaid card” (News to me, as it is my non-profit research company debit mastercard), to which tardigrade responds with "Prepaid cards not supported".
Further, signing up to an appropriate crypto exchange, submitting bank details etc. to buy Storj tokens, the other accepted form of payment, seems extreme.
So Tardigrade appears to be out of my reach, which means in turn, probably out of the reach of anyone else who could really do with reducing the costs of their outgoings to AWS etc.
The inequality of Capitalism wins again, hey-ho.
Further update; attempting to create a system backup to a second internal disk, having copied essential files from that to the first for safekeeping prior to formatting the second disk for Linux; the way that Linux indexes the second disk as if it was part of the file structure on the first disk, results in the contents of the second disk (The already backed up files), being included again in subsequent backups, therefore resulting in an infinite loop until presumably, the destination disk is full in very short time.Final nail in the coffin; I can see no way of deleting the faultily defined backup from the Duplicati schedule. So, unfortunately, I will be removing duplicati, to continue searching for another solution.