I don't think its a matter of a safety case. There is no point to it. The requirements are training to pass the test. When they are ready to pass the test they take it. What is the point of sending someone off solo. If you deem them safe to solo you deem them ready to pass the test in my opinion.
I personally think it is to much of a bag of worms to open up sending someone with a lapsed rating off to swan around solo.
ifitaint, with all respect throwing the LAPL into the equation is a bit of a misnomer. I can't find anything similar for a PPL, have you?