you can't get out of GM, you have to sweat it out and hope they pay you as much as you have invested in bitcoins - not in usd of course - before 'your contract becomes unprofitable' and they shut it down.
I read somewhere on YT of a guy who invested in GM 2 years ago and he lost 32 BTC at the moment Genesis closed his contract.
32 BTC that a freaking number :(
My guess is he went in with 100 BTC when it was like 200-300usd and got only 68 BTC back out of his 'life-time' contract. I guess the 1/3 lost goes to those above you in the pyramid scheme.
these pyramid schemes always lead to scams later on i can't even imagine the pain :(