Alien registration card in South Korea

Hello,
I am an Alien registration card holder in South Korea. I am planning on visiting China from 29th of September til the 9th of October.

I read at the top of this website that "Non-Korean applicants in South Korea are required to provide the alien registration card in South Korea (ARC) with at least 6 months remaining validity".

However, my alien registration card will expire on March 28th 2018. Therefore, my card won't be valid for 6 months after I have left Korean and arrived in China.

Does this rule of 6 month validity apply to date of travel or date of application. If it applies to date of application, then I can apply for a visa in August, while my alien registration card is still valid for more than 6 months.
Thank you for your answers in advance