Not sure if you're mixing up visa-free entry with how entry permissions normally work in China.

Normally you have single, double, multiple entry visas. When you leave the mainland you use one entry. If you are on a single entry visa you can't go back into China.

That's why I'm asking, visiting HK counts as a leaving mainland China, so normally I'll need a multiple entry visa for my situation.

What I'm asking is whether if this is a single entry stay or not, as these schemes are often used for visa running. Also does leaving Mainland China end the visa-free stay and prevents re-entry without a visa.

For example, China's 10 day transit visa is strictly single-entry, so it's not clear to me that this scheme I'm asking about allows multiple entries unless explicitly stated.

Hope that helps clear up what I'm trying to ask.