If you get residual schizophrenia can you get it again?

Quiescent period. Some people with schizophrenia stop having active symptoms but aren't completely well--still have unusual thoughts, lack energy and motiviation, etc. This is called residual schizophrenia. Yes, they are susceptible to return of active symptoms.
Schizophrenia . Is a lifelong illness, and though it may get better it doesn't go away.