I do something similar though different with my German employer. My employer lets me send my yearly bonus (or part of it) into a time account, i.e. the money gets converted into hours based on my hourly salary. Every five years, I have the option of withdrawing hours from the time account to take a sabbatical (with the normal salary payments just continuing in the meantime). And if I don't withdraw all of it by the time of retirement, the rest gets withdrawn for an early retirement with full pay.