Found the study citing 0.08. I'm still thinking this has to be a misprint? Maybe not:

Pubmed 36765111

"Of those with a delayed detectable PSA, 46% underwent salvage treatment within 10 years after RP at a median PSA of 0.08 ng/mL"

That's got to be 0.8 not 0.08? But I guess they key here is it's 46%. So it that the average of the 46% with the lowest median PSA?

What's funny is the conclusion is not advocating SRT!?

"Men who develop a detectable PSA > 6 months post-operatively may have excellent long-term outcomes, even in the absence of salvage therapy."

But an "excellent long-term outcome" for most is basically not dying of PCa. If you have Gleason 7 at age 53, it's a different long term risk than having it at age 73.