So, we're flying into Hong Kong, spending a day in HK, then planning on using the metro to cross into Shenzhen, and flying on the next day from there.
It looks like the planned integration of the Octopus card with the Shenzhen metro has not yet happened, right? So we'll need cash to pay our metro fares once we cross. Is there an ATM at the station where we can get RMB? Or should we be buying some in Hong Kong (or the US before we leave)? Where would we get the best rate?