Dallas County Jail

ok my boyfriend is in jail for multiple cases he has crimes in 3 counties (non-violent) he has theft on his hands! the first county gave him 9mths- 24mths and the second county gave him 3-23mths. well hes only served 5mths of the first county. they are trying to run this concurrent! my question is how do u figure out how long he will be away and when can i expect him to be coming back home. he has sentencing court in january for the third county and im just so confused with this stuff, i dont understand any of it, please help me out here!!