The Ending (spoiler)

No he missed his meeting with his parole officer because he was more concerned about finding his son.
Because he missed the check in with the parole officer he was in breech of his bail/licence so they came looking for him and would then be taking him back to jail to complete his sentence in full. Or something roughly like that :-/

I think he went back to jail because he wasn't working. It was a stipulation in his parole to be actively working. Since he quit and didn't tell his parole officer . he had to have him go back to jail.

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