I've been burned on this, so although it pains me a great deal to post here, I thought I'd share the info I found in the hope that no one else will lose their BTC to this scam as I can see people are currently still sending money to the shady wallet.
Key information I found after realising my error:
IMPORTANT EDIT (addition): Change your email password if you haven't already! Especially if you use the same one on multiple sites!
• BTC address for sierrahash - quickly dropped from 49BTC to around 8BTC. Got back up to 12, then 4x 1BTC withdrawals to CkCYmVScaJByuKPKr1w8HegyWdAtuV9x7 whilst no one else could withdraw
• Article claiming it was a scam from December 5th (wish I saw this first!): https://www.scambitcoin.com/sierrahash/
• sierrahash registered details from Whois. I found a fuzzy matching search and found that there have been plenty of these before that were registered in Mayfair - London (must be a place for trading houses so good cover). Will be always using data and reputation checker site going forward!
• The Facebook page is closed down and some others are talking about it on Twitter.
• SierraHash address now tagged in relation to the scam here. Also worth bookmarking!
• If you attempt to withdraw, the message below will pop up (was missing this option altogether the other day, but must have been put back in to scoop up more BTC)
Never invest your own money into any amazing free offers! If they are amazing and free, just get paid the free goodies and be content with that!
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