Cutsey as it may be converting elapsed time to rough units of fortnights, it should still be done accurately. It's been over three weeks on this process, which rounds to two fortnights (even if using metric fortnights). I realize a Windows box not being rebooted for longer than a fortnight is somewhat rare.
Whether you want to maintain humorous units is your decision. There's no question that your calculation of these units is incorrect in this instance, which is a bug.