fluctuations due to connected and then disconnected miners by Bitmain... same was in Jan...
another thing - there is a big decline in hashrate on 20:00 GMT: 11.4 > 8.7 Ph and then back to 11.6....
second hashboard on my miner went xxx at this time, but recovered soon...
what was that i wonder?
today we got 2 falls of hashrate..
1) Sia developers are testing soft fork
2) there is a bug in current algo