FS stands for "Full Scale". It is the codename of the GoldCoin Reverse Bitcoin Hard Fork project.
As far as I figured out from the whitepaper, the fork will be executed not at the current block height
but at the very beginning, at the genesis block of Bitcoin Core.
Thus the name "Reverse Hard Fork".
Since this type of fork is unprecedented, the outcome is inpredictable.
I'm hodling some GoldCoin out of curiosity but won't sell my house to invest in more.
Things are getting nastier surrounding this fork. I think I'll just sit back now and enjoy the show.