Just to let you guys know, I've started integrating other cryptos into my pool. I've put a 2% fee on other chains, but keeping the YACoin fee at 0%. 
You can keep your miners pointed at yac.procrypto.com:8336 and they'll still be fine.
Could have been someone testing their GPU setup of course.
You can keep your miners pointed at yac.procrypto.com:8336 and they'll still be fine.
This address probably ripped p2pool YAC miners from payout because of bug in earlier versions:
http://yacexplorer.tk/address/Y6Qcc77xaX4BFiBpEbMTPhunzii2UzkYtJ
I think he just rend some ec2 instances, because the 100m hashrate came so suddenly and disappeared completely in a very short time.http://yacexplorer.tk/address/Y6Qcc77xaX4BFiBpEbMTPhunzii2UzkYtJ
Could have been someone testing their GPU setup of course.
I don't think so.
After the 100m hashrate disappeared, it didn't go to yac.dontmine.me, which is known as the biggest yac pool, in fact, the total hashrate of yac.dontmine.me had a big drop several days ago, perhaps because some miners went to wdc pool. There is probably a gpu miner, but I'm sure it's not popular.