SP35/31/20 are all preorders because they use an untested chip and the specs are estimations.
It's the same chip as in SP30 so it can't be worse. Only better, but I got it now.
The SP10 was BTO because they built/tested a prototype and verified the specs before taking orders.
I'd disagree on this point in relation to the guide. The SP10 was using known chips, but it was sold with longer lead times than typical batch and preorders for future 'batches' far into the future. Those preorders are what was able to fund the next gen chip orders. It was sort of BTO, but BTO too far into the future to be considered batch.
Lol at "far into the future". All SP10s were sold with delivery in maximum 3 weeks. Even less from time to time.
Care to share what was the lead time for the AM Prisma miners? I think it's over 2 weeks now and nobody has reported getting any unit up to this point (review units don't count).