Please help me with this ATPL question

[Pilot_in_the_making]

This question came up in the air law practice questions. Apparently the answer is B, it's probably blindingly obvious, but having spent ages reading through the notes looking for that elusive paragraph with the information I need, I just can't figure out how you come to that answer:-



The proficiency check of a pilot took place on the 15th April. The validity period of the previous check was 30th June. The period of the new proficiency check can be but can't exceed:-

A) 15th October the same year.
B) 31st December the same year.
C) 30th April the following year.
D) 30th October the same year.




I know it's probably just me being thick, but please could somebody explain it to me before I throw a strop and start pulling my hair out!!!

Thanks in advance.

[Kanu]

Can't you reval/renew upto 3 months prior to expiry and it will then be valid for 6 months after the validity period of the previous check? Putting the case stated as 6 months from the 30th june?

[Pilot_in_the_making]

Thank you for the very prompt response, that makes much more sense to me now.