Note that the specs they published on the BM1385 were the "at the wall" spec numbers, NOT the chip numbers, for power.
I'm fairly certain that's false. The chip spec they posted was 0.216W/GH which translates to 216W/TH and the machine-level number they gave was 230W/TH assuming a 93% PSU; 216/0.93=232 which backs up that assertion.
The spec I saw was the 230 watt / TH "at the wall" in that chart, the one that had the S5 listed at 510 watts/TH (which IME is a hair low, but some folks have reported hitting it in reviews).
I'm not sure how much power a BB uses, the fan ALONE is about 20 watts though (presuming the use the same fan as on the S5, I don't see any reason they'd change that) and the linkage board/logic probably used a watt or two.
I suspect the S7 eats a hair less power than the S5 did for it's hair-more-than-double hashrate - sidehack seems to be ending up at pretty much the same place as I did from slightly different start points. 9-)
It is very unlikely they have S7's already at data centers. Don't really see a huge jump. Unless they put in S5 slots and did not do a big batch.
I don't see any reason why they would waste the time replacing Hashnest S5s with those S5+ things, only to have to turn around and replace them AGAIN with S7s. I do see a VERY FAINT possibility they have a "S7+/S8" design going into Hashnest.
Those "used" S5s are getting replaced by SOMETHING, after all.