Spouse renewal while out of the country

Hi, I am on a spouse visa, but need to go home for a couple of months for some hosp appointments and family events. Husband's school is telling me i MUST return to china before my spouse type expires or I will have to have the medicals etc again. I actually plan to return to China just under 3 weeks after my spouse type expires. My flight is already booked and paid for. Do you have any suggestions to help me please?