Did you read the ruling? from page 20-21. See the bold. Once APA takes over USAPA has no right to the SLI.
"The Court?s patience with USAPA has run out. USAPA avoided
liability on the DFR claim by the slimmest of margins and the Court has serious doubts that USAPA will fairly and adequately represent
all of its members while it remains a certified representative. But all the Court can do at this stage is implore USAPA to, in the words of
CAB, ?make every effort to see that [the West Pilots?] are given extensive consideration, and that their interests are fairly and fully represented? during seniority integration.
National Airlines, Acquisition, 84 C.A.B. 408, 477 (1979). And when USAPA is no longer the certified representative, it must immediately stop participating in the seniority integration