My Chinese Business Visa has date which says ENTER BEFORE 14th APRIL, I need to know is this expiry

Since I am travelling to china on 6th of April, I need to know whether i can stay there for 30 days or not. As my M type has a date which says ENTER BEFORE 14th April. So if this is Expiry date, will i have to stay only till 14th of April or if this is just a entering date so i can stay till 30th April as the mentioned maximum stay is 30 days. Please clarify on this