Seems like how raw and degraded new recruits would be would depend on how many you called up relatively to the population and years past (if you're calling a lot every year then the pool might become younger) and how soon you rushed them into battle/how much training they received.
Also, suppose you had to allot your supplies into two buckets: supplies for campaign and supplies for training. Austria may need 10 supplies per year in order to give very basic training but would only have 15 to spend....meaning they would have only 5 available to allot to the campaign pool.