Switching from an L type to a Z type

Hello,

I am currently in Qingdao looking for a job. I came to China on a 10 year 60 day multiple entry L type. I have 29 days left on my L type right now, but am trying to find a job so I can get it switched to a Z type. I was under the impression that I could just travel to Hong Kong to switch the visa, but now I am being told that I will have to go back to the USA to switch it. Unfortunately if this is the case, I will not be able to return due to financial restraints. Any information?

Thanks!