It seems possible that they made both a digital and tape recording simultaneously at that time, but feel that the new quad DSD sounds better coming from the tape master rather than the digital from that time, as you suggest. So perhaps there is some truth to both.
Incidentally, I just got an email from another former WBF member who thinks this might be the case based on what Yarlung and Mike Fremer have written, though it is ambiguous.
It's an interesting question: if they were both done from the same master tape, then the comparison is very direct. If they were done from different sources, then they are each once removed from the mic feed and additional differences are introduced to the chain. At least this is how I understand it. Happy to be corrected.
Well they use up to 30 microphones to capture the live feed and send to the R2R to record. I highly doubt the same capture was sent to a digital recorder. Why wouldn't he have just said this the first time if he already knew that the Quad DSD was better and this is the one that's going to be used for the comparison anyways? It goes from :
"The digital release was not made from the analog tape. Just as the quad DSD was not made from the analog master."
To this:
"It seems possible that they made both a digital and tape recording simultaneously at that time,but feel that the new quad DSD sounds better coming from the tape master rather than the digital from that time"
in a matter of an hour, from a guy who knew all along the quad DSD version sounded better? It went from not existing, to sounding better. Did he download the new version really quick and have a critical listening session in the last hour?
Yes this is correct and is the very reason I recommend specifically that Yarlung records recordings should be used for the vinyl/quad DSD comparison.