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The notes in the LM317A model are nonsense. PSRR is modelled, although it doesn't quite stack up with the datasheet, which states 68dB (typ) - the model delivers -55dB. For comparison, for the LM317, the datasheet figure is 57dB and the model delivered 62dB. The model behaviour overall is better than for the LM317, which doesn't model the output capacitor effect on PSRR. In the LM317A, it is modelled. The LM317A PSRR figure for when a 10uF capacitor is hung on the ADJ pin can't be achieved.

Correction: the TI LM317 datasheet Figure 8 shows about 65dB at 25?C, not 57dB, which is over all temperatures. But Figure 8 is not reliable, because it shows the additional 10uF capacitor on ADJ makes the PSRR worse, not better. Perhaps the labelling of traces is switched? Not good, TI.

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Regards,
Tony