What makes this model of "transshipment without going through customs or switching ships" even more grievous are the special privileges enjoyed by foreign-registered vessels. A ship flying the ROC flag would not only be prohibited by Taiwan from making the passage, but would also be barred by the mainland from docking.
更何況這種「不入關、不換船」的過境模式，還是外籍輪船才享有的特權，本國籍輪船受限於那面青天白日旗，不但台灣不放行，中共也不會允許停靠。