Nope they don't accept new members. They are now called coinsbank, not Bit-x although they still have Bit-X name on their signature thread. Also, you're a newbie. Even if people leave the signature campaign, you wouldn't be able to get in.
Signature campaign is just not for everyone. You would need to have a high rank member to get some real money out of it.
Yeah and in signature campaign that is not enough to earn 0.3 btc in a week you must have a lot of source such as doing task for rewards, working very well in trading.
offering your services and skills to the people here and other ways also.
Ofcourse, someone can earn 0.03btc or 0.05btc in a week with a signature campaign but someone obviously cannot earn 0.3btc in a week if he just depends on signature campaign, if signature campaign could earn you that much in a week then it wouldn't have been called an extra income.