They didn't pay their developer and copied the whole commit for them to be able to use it. This is a clear sign of a "SCAM". This is now their Official Development page : https://github.com/BitcoinInterestOfficial/BitcoinInterest . It was updated last year.
These guys can't be trusted. Don't be fooled by airdrops and forks. If you buy into it, you'll lose what you have.
Anyone can post things on github, that is FAKE. Our Dev. team is hard at work, Source code will be released soon. Please do not trust any source code claiming to be ours unless it is linked to from our official site http://bitcoininterest.io.