Questions on "good time credits"

What is the name of your state?CA

My husband is incarcerated, while incarcerated, he got "another case" he has a total of 14 years time. The first "good time credits" were taken due to his behavior. When he got his second strike, he was told he has to serve 85% of his time, and he is eligible for 15% good time as long as he stays out of trouble etc etc etc.

He has not been given the opportunity to get his good time. They maxed out his sentance (of which he has only lost 30 days good time) but he has taken it to Sacramento, and they denied his appeal to get his "good time" back.

They told him that according to the California Code of Regulations, Title 15 codes 3001, 2269.5, and 3370 state why he wont be getting his time back.

I can only find 3001 code under the penal code, title 15 and the CCR.

Is there any advice from anyone that I can get to try and help him get his time back?

Also, he is thinking of filing a Habeus Corpus, to take it to the courts. He took a plea for both of his sentances, can the court pull his plea if he takes it back to court?

Any advice would be greatly appreciated.

Thank you