MichaelGab,
I am not aware of any "immediate" discharge cases but it would be interesting to find one. As you said, there are usually some sort of disciplinary charges awarded prior to a discharge from the services. As per below.
Regards,
Gordon
Albert was so poorly behaved a sailor that after various periods of imprisonment including an occasion where he was convicted for 6 months of hard labour and prison for striking a superior officer, leaving him “dismissed” from the Navy and not joining the Royal Fleet Reserve like many men who would become recalled for service in 1914.
He was fortunate for his “Dismissal” to become a “Discharge SNLR” meaning Services No Longer Required, a more polite version of firing a Sailor, but left him unable to claim pay, pension or assistance.