It just says L visa, not spousal L visa. When I apply for an L, I tick two boxes, one for visiting a Chinese relative and the other for touring. The only difference is the length of the visa. At least 6 months, maybe 1 year, according to the attitude of the PSB of the Chinese relative's hometown. Going through passports faster than the average is nothing compared to advantages such as avoiding medicals and visa runs to HK/UB. As for release letters, they don't apply.

I reckon there are at least 30 foreigners teaching on behalf of the three Yuncheng agents on L or X or F visas. The local PSB turn a blind eye. If they dare to take action against foreign teachers teaching illegally, they will be fired by the mayor. I guess the mayor and the PSB get regular bungs from the three local agents.