Most of the tracking number emails I've received from Bitmain arrive between 5AM and 8AM ET, so if they do ship on the 14th, we should know within the next 16 hours.

Ugh! It's 3:11AM July 14th Beijing time, why haven't they shipped yet!?

/kidding

It sounds like all of the $400 coupons expired on June 27th. As of now, the cheapest place to get a new S2 is Amazon. They're usually about $120 cheaper there. There's also batch 1 S3s available in 1-packs or 2-packs, but they're not discounted like the S2s.

If you're dead set on getting an S3 (batch 1 even), we have 6 remaining on Amazon - but they're more expensive than purchasing direct with bitcoin (whenever batch 4 opens). Based on the last couple of days, I don't expect them to last through tomorrow.

They'll probably wait to start shipping batch 1 before opening a new batch. I'm hoping batch 4 goes straight to their "ships within 48 hours" phase.

Remember when KnC advertised Q1/Q2 for Netpunes? I'll happily take this 10-day window over that.

Lightning... That would explain a lot. I assume you've tried bypassing the front panel's Ethernet port and connecting the network cable directly to the Beaglebone. If not, try that.

Here's what I would try next:
Revive a Dead AntMiner S2...

I think networking configuration is about 1000x more likely. I sell many of these on Amazon and offer support too. Every problem I've dealt with has been network configuration based. Hopefully OP responds and we get to the bottom of this for him.

I wouldn't flash the SD card just yet, it's highly improbable that 3 of them were all bad. I've dealt with dozens of S2s without ever needing to flash the SD card.

Can you describe what you mean when you say that they won't connect to the network? Also, from a computer running on the same network, please open a command prompt and run "ipconfig /all" and post the results here. All Bitmain hardware comes with preset network settings that won't work if your router's IP address isn't 192.168.1.1. Many routers use 192.168.0.1 or 192.168.1.254, which could cause the problem you're describing. Additionally, please confirm that you don't already have a device running with the same IP address of 192.168.1.99.

I have a strong feeling that your problem is not with the hardware ;-)

I really like btcinvest.net's calculator in comparison to the others I've seen. I estimate that with future diff increases of 15% (based on last 6 months), your return on the $550 miner would be about $400 - assuming 100% uptime. Now, if you're into mining and hoping for a profit - then you're hoping that the future diff increases won't continue to be 15%. To break even, they'd have to be at about 10% from here on out.

http://btcinvest.net/en/bitcoin-mining-profit-calculator.php?diff=16818461371&dcosts=550&diff_mincrease=15&blpbtc=25&dhsmhs=478000&diff_mincreasedecrease=0.0&btcusd=600&dpowcon=366&btcusd_mincrease=0&pcost=0.13&calcweeks=15&dleadtime=1&action=calc

It will be Monday. Bitmain hasn't let me down yet. 

Not that this should come as a surprise, but I asked Bitmain about the launch date of the S4 and they wouldn't give any details... but they did refer to it as the "S4" - so at least we know we're calling it by the right name  

Also, $1499 $1489 now on Amazon

Yep, with plenty of room for overclocking if you want too

I do offer support upon request, but I've been fortunate and very few people have needed any. Those who have needed help were mostly unfamiliar with networking. I've only had 1 customer claim to have a DOA unit and I refunded him in full upon returning it to me. I was able to get the unit running right away, so I'm guessing it was another networking issue 

I'm pretty sure all of the $400 coupons expired on June 27th  

$1450?... I don't know if I'd trust a seller without any feedback yet. I can discount by $110 though now! New price is $1529.99. I also have a bunch of single batch #1 S3s for sale (and 2-packs), but I would recommend buying directly from Bitmain (minimum order of 2) if you have the bitcoin since they're cheaper than I can offer when accounting for Amazon fees.

Other than their amazing track record, Bitmain probably doesn't have the facilities to host all of the miners they make.

Most people who accuse mining manufacturers of holding back inventory don't realize the infrastructure that would be required to do this. If I had to guess, Bitmain probably has 1000-2000 machines running at all times. They would hook up the brand new ones to mine and then sell the tested ones that have been running for the longest (off the shelf). This would match our observations about their recently increased hashrate as well as allow them to accurately promise shipping dates to us. As their production capacity increases, the amount of time each unit is tested for would decrease since they wouldn't be increasing the size of their mining facilities. They're likely in the process of filling their racks with S3s right now and will start shipping as soon as they don't have any more room.

The Bitmain testing phase is well known and most often appreciated as it is reflected in the quality of their equipment. Any bad devices would likely be found during testing and not sold. For reference, I've purchased between 300 and 400 btc worth of equipment from them over the last 4 months and have less than 3% failure rate. That is significantly better than any other manufacturer I've dealt with.

If you're interested, I still have some 1st batch S3s available via Amazon. They will be among the first to ship from Bitmain when expected shipping begins this week.