Hi,
Is your PL quota deduction upto is 31.12.9999 ? and any ceiling is there that total 30 or like that ? because in your screen shot for 2016, it is showing 01.01.2016 to 31.12.9999.
you have to check in the TE log only, why system is giving 23.5 days quota only. please the share TE log screen shots for better understanding.
Best Regards