This was not a new tariff.  This was a reclassification of miners under non-programmable, non-data processing electronics.  That is true of these devices and the reclassification occurred on June 8th, 2018.  Not defending some of the trade issues that Trump will bring the US, but this was not part of his work.  


https://rulings.cbp.gov/search?term=ANTMINER&collection=ALL&sortBy=DATE_DESC&pageSize=30&page=1

There was a request to have miners remain under tariff classification 8471.50.1050 May 29th, 2018, but this was denied.

The invoice shows the old tariff classification.  Customs changed it when they saw ANTMINER on my invoice.

https://imgur.com/a/h6wGRgk

Just got off the phone with customs.  They are reclassifying the tariff association from 8471.50.0150, what is on the invoice from Bitmain, to 8543.70.9960 because "ANTMINER" is on the invoice as of 8/23/2018.  This is for all carriers into the US. DHL, UPS, etc.

https://hts.usitc.gov/?query=8471.50.0150 - High Level:  Freely programmable data processing electronics - 0% extra fee
https://hts.usitc.gov/?query=8543709960 - High Level: Not freely programmable specialized mining equipment - 25% extra fee

https://rulings.cbp.gov/search?term=ANTMINER&collection=ALL&sortBy=DATE_DESC&pageSize=30&page=1

Unless Bitmain changes their invoice to not say ANTMINER, but instead calls it general purpose computer, or something else, customs is now changing the tariff association.

z9 mini default work: 10k sols
z9 mini OC avg.: 16k sols (1.6x the default)
z9 mini default watt: 300w

z9 default Work: 40ksols  (Or 4 minis.  Not likely to pull any surprises, as Bitmain is pretty consistent with their delivery)
z9 plausible OC: 64k sols
z9 default watt: 1150

z9 mini price batch 2: 850
z9 price: 3400/4 = 850

So, price wise you are paying the same for 4 minis as 1 z9.  If you have coupons from the first batch purchase you are probably better off buying the minis, imo, since you can only use one coupon per miner.  I just grabbed 5 minis in batch two at, before tax/shipping, 600 a piece using 1 coupon per miner.

Just started getting a ton of rejected shares from Suprnova.  Been working fine since Monday (6/26):

https://imgur.com/wRclvKo


EDIT: Moved to ZHash.pro. Getting no rejections from their pool.