Well, your case is really a tough one, and I'm not sure what I'd do in your case -- I'd be kinda "on the fence".
Can tell you what I've done since my uPSA started going detectable a few years ago. I've kept up my 6 mth appts. with urologist I've had all along. I've closely monitored my uPSA and tried to do everything I can to make each test meaningful (avoid biotin, keep similarly hydrated before blood draw, etc.). I even went off TRT, probably forever, Dec. of last year when I thought I was getting a spike in uPSA. You can see this in the last half of 2018 readings in this uPSA chart I keep:https://i.imgur.com/ogdl0hc.jpg
Since then, I've kinda seemed to stabilize. If I see a definite trend up, that doesn't seem to be just month to month variation, then, yes, I will start pushing ahead with an RO. Probably in the .10 to .15 range, I dunno. My urologist says unless I was in the .4 range, the current scans would not be of much help. So guys like us are just flying blind as regards knowing what is really going on. Fact of life. But really unsettling. I am just trying to get used to it.
I suppose you could try closely monitoring for a short period and see if you are going to stabilize. Some studies show that a certain percentage of recurring men have this happen. I am age 70, so as things stand now, I'm likely to die of something else. My uro last visit said exactly that.
Please keep us posted of what happens. It will help others.
age 70 now
Jan '08-'11 PSAs 2.2 2.5 2.7 2.6, DREs-
Jan '12: PSA 3.6, DRE+
Jan '12: MRI inconclusive
Feb '12: PCaDx pT2a, 4/12+ (3 @ 3+3, 1 @ 4+3); 3% tot cores; bone scan-
Apr '12: RALP; 3+4=7; pT2c pN0 pMx; 30%; 3mm r lat margin of 3+3=6 so pT2+; EPE-; PNI+; 8 LN-; SV-
TRT 03/'14- uPSAs: <.015 til 02/17; mostly .020-.030 then .048 on 12/1/18; off TRT since 12/2018 and uPSA settling in mid .030s