Bang up

Perhaps exclusively used in Great Britain. Refers to the period in which a prison inmate is confined to their cell, such as during nighttime hours. Can also be used for a more specific personal restriction of movement - e.g: solitary confinement. Often used by former inmates outside of the context of prison to refer to a curfew or restriction of movement in a residence. For example, a hostel for vulnerably housed people might apply a curfew at 9pm, which may appear to draw a parallel with the prison curfew system. When used by someone outside of the prison system, it can far more generally refer to any time spent in prison at all.