Very pleased to hear your good news.
My hospital only tests to 0.1, so <0.1 is classed as undetectable. The top cancer hospital in Britain, the Royal Marsden only tests to 0.04, but other labs test to multiple decimal places.
One urologist and one oncologist told me ‘super sensitive assay’ to umpteen figures is a waste of time, and another oncologist told me it is only of limited use.
So keep calm and keep on recovering.
Cheers, John.