I already have a valid 10-year L-type Chinese visa obtained in 2018 when I traveled to China last year. Now I am planning a tourism trip for 2 weeks followed by a stay in a university where I would lecture UNPAID for 3 weeks (total of 38 hours).
The main purpose of the trip is tourism but, from my readings, I think that I need an F-type visa for those 3 weeks.
Question 1: Can the Chinese visa office issue two visas that are valid at the same time? (A new F-type and my present L-type)
Question 2: Could my L-type visa be suspended and then reinstated?
Question 3: If I have to give up my L-type visa, can I travel for 3 weeks on the F-type?