something is definitely happening. All the major pools today are hit by large influx of hash for 30 minutes which then disappears.
The difficulty rises during the 30 minutes, but when the hash disappears difficulty does not go down fast enough.

So smaller miners who stay on the pools are hurt bad, my mining return is very bad today.
Difficulty going up and down from 32000 to 42000 to 31000 within 30 minutes is not normal

If this continues BWK is no longer viable to mine. The algo seems not to adjust to hashrate peaks well.

Just look bsod.pw, umine.org and unimining.net. They cover around 80% of total hashrate but all 3 no blocks found last 20 minutes, just after a big hashrate peak.
Difficulty is now down from 42000 to 27000, soon we see the hashrate spike again. (nethash down from 1.8 Th/s to 970 Gh/s)