An aditional part of 'Jankers' was the 'defaulters' parade'
At fixed times during the day, usually when the rest of the unit were temporarily 'off duty', the bugler would sound "Defaulters" at which, the man under punishment was obliged to present himself, in the correct order of dress, to the Guard Room for inspection or 'detailing'.
Needless to say that lateness, faults etc. could result in further punishment (more 'jankers').
Oh yes, and 'Defaulters under punishment' were barred from the 'wet' canteen.

Regards

Walrus.