Reliable real-time kinematic positioning requires the occurrence of incorrect integer ambiguity estimates to be limited to a maximum tolerable rate. For long baselines this usually implies long convergence times due to the presence of atmospheric delay parameters. Several simulation studies have shown that partial ambiguity resolution (PAR) techniques are beneficial in terms of faster solutions, since it is more likely that a subset of all ambiguities can be reliably resolved rather than the full set, but they also result in a positioning precision that is inferior to the one after successful full ambiguity resolution. We analyze the impact of PAR on the positioning capabilities of dual-frequency single and combined GPS and BDS on a long baseline. It will be demonstrated in numerical simulations that the time to reach centimeter level positioning results can be expected to be clearly reduced when using PAR techniques, in particular for the combined system. This will be verified with one day of real global navigation satellite system data from an 88.5 km baseline in the area of Perth, Australia.