...The cause for the latest delay is that we recently discovered that said third party had ordered largely substandard inappropriate substitute parts for our boards, not the ones we specified. We are lucky we found this out when we did. Going ahead with the manufacture with the wrong parts would have caused all sorts on unknown instabilities on the boards. People may well have received them sooner, but there would be a large chance they would not work properly, not get decent hashrates, and perhaps not work at all, or break soon after being plugged in. Dealing with this problem after the boards had been made would have been a nightmare.
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Barntech
I feel your pain, and think you've done absolutely the right thing, both in making sure the parts ship to spec, and clearly communicating the delay. The insight into the production process is one of the most intriguing parts of the scene, watching how the process changes and evolves for each gen iteration. Can you offer an insight into which part in question was affected, for those of us who are following development with curiosity?
Good luck getting them out.