The requirement is still in the CAAC AIP
4.8 In order to facilitate radar identification and air traffic control, aircraft shall establish contact with the next ATC unit at least 3 minutes prior to crossing such transfer of control points as BEKOL, TAMOT, SIERA and SIKOU.
There is also a requirement to have established contact before entering Chinese airspace.
Practically HKATC will do the ATC hand off by phone, so China will want to radar identify. HKG will transfer you well before the waypoint.