Edited this to update. It looks to me like you asked the question twice with two different sets of numbers.

If all those tests were 0.01 I'd and now you're getting <0.1 I'd suggest the new test is not ultrasensitive, in other words the two numbers might actually agree. < 0.1 could easily be 0.01.

#1 I'd take a deep breath as the new test as written <0.1 isn't really telling you anything other than you're not over 0.1.
#2 I'd call my urologist and see what they had to say, ask for his on call or person listed as replacement/stand in while on vacation.
#3 I'd suggest having another test in 2 or 3 months with the same (new) lab and look for movement in the number. If it's still 0.1 then it's likely not increasing. ...or go back to lab #1 and see if you still get 0.01. (second method preferred)

The issue here is making sure you're comparing apples to apples.

To answer your question literally, I've always understood anything in the non sensitive test realm less than .2 (post surgery) to be considered negative (at least the government thinks that). However, I believe that to be based on old technology testing wise.