The likelihood of deportation rather than a standard release into the community is high, and preparing for that reality now is important.
When an undocumented person is booked into a Texas jail or state facility, ICE typically places a detainer on them during or shortly after the booking process. That detainer is a formal request from Immigration and Customs Enforcement asking the facility to notify ICE before releasing the individual and to hold them briefly so ICE can take custody. If an ICE detainer is already on file, and in your husband's situation it almost certainly is, he will not walk out of Pam Lychner into Harris County or Humble. He will transfer directly into ICE custody when his sentence is complete.
From ICE custody, the process typically moves toward deportation proceedings. Depending on his immigration history, his country of origin, and whether he has any legal avenues available, the timeline and outcome of those proceedings can vary. Some people are deported relatively quickly. Others have grounds to contest removal and the process extends through immigration court.
The most important step right now is getting an immigration attorney involved if one is not already in the picture. An immigration lawyer can determine whether your husband has any legal options to fight deportation, whether any relief is available based on family ties or other factors, and how to navigate the ICE detainer process. That legal consultation is time-sensitive and should not wait until he is close to release.
Understanding what is coming and having a plan in place, however difficult that plan may be, puts both of you in a better position than being caught off guard when the sentence ends.