Reference AWS D1.1-2010, Table 4.11, footnote d: "Also qualifies for welding any fillet or PJP weld size on any thickness of plate, pipe or tubing."
My understanding is the welder is qualified for all fillet and partial joint penetration groove welds by successfully passing a CJP performance test of any thickness. The size of the PJP groove weld and the fillet weld size are not limited nor is the thickness of the base metal limited based on the performance test passed.
Best regards - Al