TB test read earlier than the 48-72 hour window

Hello colleagues.

So here is one for your, see if you can answer. I had a PPD planted at 6:30 pm Wednesday, came back on Friday to have it read. It was nice and negative. Time of the reading 6:17 pm, full 13 minutes earlier than the recommended 48-72 hour window. I asked the doctor if the test was going to be rejected because it was read 13 minutes early, but she said no, it shouldn't be a problem. I never had a ppd read before the 48 hour mark, usually i was close to day three than day two, but this time I showed up 15 minutes earlier, thinking I had to wait, but they took me right away, read it, stamped the paper and sent me off. The whole appt took less than 5 minutes. I lingered in the office till 6:30 just in case ( and no I didn't indurate at the 48 hour mark) but the receptionist kept on asking if I needed anything else. Geez, they really were in the hurry that day. Anyway, I emailed my employer the result, and the reply came back that it was read 13 minutes early. No word on whether they would reject it or not. The thing is , this is my second ppd in two weeks because the first one was documented incorrectly by the clinic so the test was rejected by the HR. I called the HR this morning. The nurse who answered did say that the reading sounded ok and that it shouldn't be rejected. Just to be safe I called another urgent care clinic and consulted them. They said the same thing, 13 minutes wasn't a big deal and the reading would be accepted.

What are your opinions? Experiences? Have you read anyone's PPD where it was outside the 48-72 hour window?

much appreciated.