Cultural exchange - Chengdu

Hello, I am a British national and have a cultural exchange in Chengdu so I assumed I would be applying for a F visa. However I have gone to the consular office and they told me I need to have a return flight booking I can give them and it would be an L type I have to apply for. I am not going for tourism, and what I am reading online seems to be inconsistent to what I am being told. Does anyone have a similar experience or some advice to give?!

Samsta