It takes about half a year to train an infantryman fully, including short-range scouting. Make that 9 months in peacetime due to weekends and lower intensity.

The problem with conscript armies is that the army leaders want to use conscripts as active force personnel, they don't consider conscripts to be men who get a training and then leave. As a result, conscript training is cut down to press at least some months of reduced effectiveness active service out of them - and many conscripts are being mis-used as cheap forced labour to be used on the most stupid jobs with minimal training.

The political leadership can force the military leadership to consider conscripts as men to be trained for war, and nothing else. That, after all, is the purpose of conscription in wartime, true to Scharnhorst's idea.

Allow the top brass in uniform to consider conscripts as cheap unfree labour that's available no matter how attractive the service is and you'll end up with a ####ty for of conscription.
Force them to train the conscripts and then release them - you will end up with a huge pool of trained reservists when the #### hits the fan.