About HDAC you guys are talking about...

They did a algo-swap from Lyra2Rev2 to Skunk
Source: https://hdactech.com/en/News/news.do?mode=view&articleNo=6951

Quote: The change will be applied from block number 151,880, and it will be applied on (GMT + 9) October 22, 2018.

All the guys mining there did just come "here" to us.
That's why the hashrate went up...

Just asking myself how this coin had this hashpower...anyway.
It is what it is....